Replacing Coolant Temp Sensors | Page 2 | FerrariChat

Replacing Coolant Temp Sensors

Discussion in '348/355' started by 3forty8, Jan 26, 2009.

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  1. f355spider

    f355spider F1 World Champ
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    #26 f355spider, Jan 26, 2009
    Last edited: Jan 26, 2009
    As the "beta tester" on Dave's new connector kit, here is what I learned from that previous method (which I admit I was a big proponent of in the past):

    1) You cannot reliably clean the female part of the connector, because it requires brushing to break the surface tension with the contact cleaner. This requires disasembly of the female pins from the plastic housing. I looked at several "cleaned" pins (cleaned while still in the plastic housing), but removed and inspected under an 8X loupe and they had quite a bit of crud and yellow jelly looking stuff that I can only surmise was some sort of combination of old dielectric grease and Stabilant 22.

    2) The old female connectors lose tension from use. Just compare a new one to old. I took some old ones and tried slipping them onto a business card, they fell off!

    3) If you have any cracked, torn or ripped boots, you WILL have corrosion at both the male/female connection point, but more importantly, at the WIRE to female connection CRIMP. This corrosion even creeps under the insulation, and requires that you clean and brush the freshly stripped wire repeatedly with contact cleaner, before you can crimp a new connector on.

    4) Stabilant 22 may initially improve a connection, but based on the goop I examined, and Dave Helms has seen under a microscope, it is probably inhibiting the connection in the longer term. Dave found a hard film formed from Stabilant 22 that could be scrapped off the metal surface.
     
  2. fatbillybob

    fatbillybob Two Time F1 World Champ
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    I agree with len. That little pipe has got to go. I'd carefully unscrew it now before you have to end up chasing it out. It is a known failure point and is not due to bad coolant changes. Its a bad design of dissimilar materials and electrolysis. Just put a new one in and change it out as a wear item. These cars are old. Old 3forty8 has pretty big hands I'm surprised he chose this route. Good job! The primary reason I like taking the plenum off is it allows inspection of other areas like the hose on the T-stat that in many cars is also 20 years old. It is another failure you don't need and disguises itself as a waterpump leak which is an engine out fix. The last thing you want is to be fooled into pulling your motor unless you like that sort of thing.

    As to Stabiant 22 I think Dave and I were on the same thread about that not too long ago in the tech section and came to a similar conclusion. Out of laziness I gave up on S22 and found that if I just cleaned the connectors regularly with electrical contact cleaner as part of my prerace inspection and let them dry until the end of my inspection and brake bleed before reconnecting them, they worked fine. No S22 was needed so I stopped using it. I still have a lot left. I am not sure if there is an advantage over just cleaning in a car that sees less maintenance. Probably there is. The mental problem I had with S22 despite its great initial results was that is was kinda vaseline like and I used it liberally. The Ferrari connector are so bad dirt gets in them. So then I had dirt in there all stuck to the vaseline. It may have worked but looked like it should not work. So I just ended up cleaning regularly instead. Problem solved. One thing I never did try but thought about was using big heat shrink tubing and shrinking it around a newly clean connector. My idea is that the heat shrink would put additional pressure on the connector to keep it clean and keep it tight. Then you would just razor it off for access. Most of us never drive ferraris in the rain so water would not be an issue. Someone should try that with a 348 the king of crappy connectors.
     
  3. No Doubt

    No Doubt Seven Time F1 World Champ

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    #28 No Doubt, Jan 26, 2009
    Last edited: Jan 26, 2009


    You bring up some good points, but part of the core problem is that the vast majority of the entire automotive world mis-uses dielectric grease.

    "Dielectric" means that something "does not conduct electricity." Dielectric grease is a water sealer/repellent meant for the *exterior* of rubber shields for electrical connectors (e.g. spark plug boots), but is not meant for the actual metal electrical connectors themselves. It's basically vaseline...which doesn't conduct a shock/charge. Pull out your handy ohmeter and you can verify the above on any wire-length string of vaseline.

    But even manuals for changing spark plugs will incorrectly suggest using dielectric grease on the metal connectors of spark plugs, rather than on the *ceramic* to rubber sparkplug-to-plugboot interface (where the dielectric grease will keep water away from the spark plug).

    So yes, the improper use of dielectric grease is going to leave a non-conductive residue that will harm your automotive electronics. Sure, you can *correctly* use dielectric grease on external rubber interfaces...but if you start putting dielectric grease incorrectly onto metal conducting surfaces, you are going to find electrical gremlins charging into your Ferrari.
     
  4. rivee

    rivee F1 Rookie

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    Somebody stole Dave Helms posting in Ferrariads about the Motronic gold connectors..

    Where did it go?
     
  5. davehelms

    davehelms F1 Rookie

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    Let a mechanic play an advertising / sales guy on the computer and what do you expect?! I must have had the wrong boxes checked and when someone "Commited" it went away.... Wait until the gal that does my ad work finds out I am doing this again...I'm in deep trouble!

    Dave
     
  6. davehelms

    davehelms F1 Rookie

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    Thanks Eric. Truly the last thing I wanted to do was be involved in parts manufacture but when I couldn't find quality, I decided to quit griping about it and build it.

    In this day and age the MADE IN USA on the label has multiple positive implications once again and should be advertised in CAPS! The engineers took a "how can we help you" stance and a "no, we do not make that....until now, we'll figure it out, give us a few days" attitude that has not been seen in the market place since our folks were in charge. I am proud to be able to work with Pro's like this and their pride shows through in the components THEY are making.

    Fatso's statement is right on but in this instance is caused by dissimilar elements and heat. The aluminum nipples were not anodized and the raw aluminum was tightly clamped to a high carbon content rubber mixed with a very high ambient and contained heat in this area. The Silicone is a highly inert substance and is quite friendly with the aluminum castings its clamped to. These bleed hoses to the coolant tank are the first to go on EVERY model, I will post a photo of the last 308 housing to give you a better fell of what they look like when the corrosion is all removed.

    No Doubt,

    That's the upside, you are not stuck with the OEM components any more. They are all used up and done, I found the engineering drawings for these and the total life expectancy is 5 removals and 5 installs...10 total, that's it...I exceeded that when the cars were still in warranty let alone pulling the engine to service it! The dielectric grease was put in there to keep moisture out but ended up holding moisture on the connectors when the boots failed and got in there over time from leaking components near by.
    Per my father, the Apollo Project started off using dielectric grease on the command module connectors but that was abandoned when it was identified the grease had hydroscopic properties and was causing issues it was intended to prevent. They went dry with Gold plated connectors...sound familure? You have him to thank for this kit as I am a good listener and am just following what he did 40 some years ago.

    As Hugh stated, I have inspected these old terminals under high power magnification. On freshly cleaned and S 22 treated examples there was a hardened film that could be flaked off. I have stated it before and still believe the Stab product is good, but it is a fact that it is misused and I for one still do not know how to use it properly and this resulted in worse connections that before the applications. FBB's observation is correct, clean with nothing added is better in this instance. Hugh's statement is correct in that there is no reliable way to clean the female connector, try as we may, scrub the tar out of it with anything you want (I tried brake cleaner, carb cleaner, contact cleaner...if it was in the cabinet I sprayed it on) then cut the old terminal off and inspect it under high magnification...the corrosion is still there! I designed and am fabricating special stainless and brass brushes that do a very good job at cleaning the male pins where there is access to all of the exposed facets of the pin. Cleaning these is fairly easy and if one is willing to take the time to do it right, these can in most cases be made as good as new. I have yet to replace a temp sensor on any model since the 348's were new, Bosch did a pretty good job on these components.

    The trick to this kit was designing tools to do the job where one didn't cause more harm than good, ohh you should have heard the names Niki called me when we first started with this quest.... started off with 10 perfectly nice fingers, finished days later on the first few cars with half of the bandaged up! Hugh was the final tester to see if this was possible as a DYI project. It is not for everyone and requires a great deal of patience to do it correctly. I choose Hugh to test this because of his problem area's that have been a focus for years...I wasn't looking for one with easy problems, I wanted the car with UGLY issues and someone with a "I'll try it but I don't believe it" attitude to test this procedure. Hugh's procedural questions and feedback invaluable in the testing of this kit. I knew first hand how the terminals worked as I have been working on this for better than a year now, the question was can a procedure be designed for a DIY install. Hugh says yes. Second area of concern was reducing the cost by providing cheaper tools....that was abandoned early on and a decision made that this was going first rate in quality or not going at all as it takes Pro level tools to do that level work. That said, many should leave this job to their mechanic as doing it anything less than perfect the first time with provide results on the same level as the effort given. Time will tell but I have a good many "problem child" cars on the road now that have been trouble free for full driving seasons with this procedure implemented and the kit installed that would normally have exhibited problems a couple times a week.

    My last quest is to find a machine shop to make the tools I now do one by one on the lathe at home and at the shop. I had no want to have a shelf full of special tools made for this job before Hugh did the testing....those shelves are full of hundreds of feet of prototype silicone hose from early in that process that for one reason or another fell short of my goal.... The old Ferguson tractor will be styling and the rest goes in the trash can to make room for these parts.

    Dave
     
  7. gothspeed

    gothspeed F1 World Champ

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    Great thread with great info :)!!! As mentioned by Dave ......... in Aerospace .... connector pins are dry crimped, dry connected and use good materials ....... preferably precious metals ......... generally pins are gold plated and crimped to silver plated oxygen free copper ............. but depending on application ..... can get even more exotic, using 'Solid Gold'/Silver .............. and now 'Soul Train' comes to mind .............. :cool:
     
  8. 3forty8

    3forty8 F1 Rookie
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    Just got off the phone with Daniel and ordered one - a couple more coolant flushes can't hurt when I replace it this weekend.

    Dave, looking forward to availability on the hose and connector kits - please keep us updated!
     
  9. f355spider

    f355spider F1 World Champ
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    Unfortunately you did not read my entire post and are focusing on one aspect. The misuse of dielectric grease is only one (abeit minor) aspect of the entire connector problem, as outlined by Dave Helms above.
     
  10. f355spider

    f355spider F1 World Champ
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    #35 f355spider, Jan 27, 2009
    Last edited: Jan 27, 2009
    To further help Dave Helms explain why one might need this kit one needs to detail the problems with the Amp connectors:

    1) Engine heat and age cause the boots to crack and tear, allowing moisture to intrude.

    2) Moisture causes corrosion at both the connection point of the male and female connectors, but also where the female connector is crimped to the wire. Most of this requires inspection with a loupe or microscope to see the problems.

    3) Short service life of oem connector pins. 10 cycles is the design life, then the nickel plating starts wearing the the tension starts loosening on the connectors.

    4) Out right broken connectors are easy enough to find and repair, but most of the issues this kit can correct, deal with poor contacts causing intermittent problems, or problems cropping up only under a specific set of conditions. Stuff that can drive you nuts trying to trace or find, particularly if you do not have the Ferrari factory break out box.

    How Dave's kit improves upon oem:

    1) Boots made of a silicone material with higher heat resistance, and tigher fitting at each end, to keep out moisture.

    2) Connectors pins with a rated 100 cycles life, gold plated at the contact point.

    3) Dave's detailed instructions and tools for not only properly cleaning the male portion of the pins, but also properly prepping the wire before crimping the new gold plated female connector. And proper cleaning techniques for the plastic housing the pins will be reinserted in.

    4) Professional quality tools, that make this job infinitely easier than it would be otherwise.

    Obviously one could renew everything with oem components and get the similar results, but for how long? Dave's hard work and tireless efforts at sourcing around the world has brought us a "ready to go" kit that gives optimal results that should last for many, many years.

    Full disclosure: Yes, Dave is planning to charge me "cost" on this kit for assisting with feedback and suggestions, but let me tell you, I would happily pay full retail and then some, for what this has done in correcting my cold start idling issue, which I will go into further in another post. This kit works, and I am convinced it will prevent me from experiencing future problems as I found many connector pins that showed corrosion either at the wire contact point or at the connector to the male pin.
     
  11. rivee

    rivee F1 Rookie

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    Great post Dave.

    Thank you for your continuing effort to make our cars better and last longer.
     
  12. saw1998

    saw1998 F1 Veteran

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    +1000! Dave is an absolutely amazing man! We all owe him a big debt of gratitude. Now, if he would only let me clone him....
     
  13. davehelms

    davehelms F1 Rookie

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    #38 davehelms, Jan 28, 2009
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    Two good points. Hugh would have been money ahead had he waited and paid full price for everything. I would hazard a guess and say he has no less than 3 hrs long distance on the phone and double that again in time writing emails, that will have him thinking twice before saying yes to type of thing again. One cant put a price to this kind of help and the procedure write up isn't done yet.

    Last night I sat down for the first time since this began and put final hard costs to just the components and tools for this kit. Half way through the testing I had considered abandoning the research and simply buying new harnesses and throwing them in.... I knew I shouldn't have done the math with Kris near by. Granted this would reset the corrosion time clock but still does not address the cycle life of the connectors let alone the quality issues resulting from using cheap components in the first place...how many of the connectors are really "tight" on the pin when they were new? If the attached photo is an indication of a standard then the answer is 33% were.

    It would only be a matter of time before one of two things happened, Ferrari would raise the price of the harness to some insane figure (think it wont happen?) or I would pay for a new harness, the labor to strip the whole engine down to install it and then have to spend countless hours trying to identify a rouge problem that COULDN'T be a result of a bad connection due to a loose fitting connector because it is a NEW harness. The photo shows exactly what put me back into research mode and the decision to follow this through to the end. Obviously a virgin connector as installed by the factory, not a normally removed connector that has seen numerous cycles of removal and install..... What makes the center connector better than the outer two? Quality control, nothing else. Think a new harness is any better?

    In this day and age "parts replacing" has become the standard method of repair and in turn has lowered the quality and reliability of these cars even further than when they were new. The design is genius, the cars are the best in the world and the parts are, simply put, Hideous. I started publicly griping about it two years ago and am now doing something about it. In the case of the harnesses, the sheathing material of the 355 is leading edge technology for the era and in most cases still perfectly serviceable as are all of the sensors and components. I have come across some harnesses that had crumbling wires inside but this was due to heat issues and not from bad wire. In that case the harness has to be replaced and the source of the problem addressed but I for one will be replacing every connector on a new harness before it is installed based on my findings from this research. From a conductivity standpoint alone the difference is very note able. I have never been able to get the exact figures Ferrari wanted to see when a breakout box is used to diagnosis a problem...until now. The first test car was a 95 355 GTB that I thought ran PERFECT.... so I thought at the time, the random CEL really was telling me something. This isn't my first rodeo with these cars but obviously my butt-o-meter needed recalibrating!

    I have to work on finding a way to post a thought in on sentence or less, talk about long winded replys!

    Dave
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  14. FandLcars

    FandLcars F1 Rookie

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    Dave - I always enjoy reading your posts, and part of it is reading your experiences and your thoughts throughout the process. Thanks for taking the time to do it! :)
     
  15. gothspeed

    gothspeed F1 World Champ

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    +1 .......... great illustrative pics there Dave :)!! That is a great find to see the blades have lost their tension ..... along with a great fix .......... gold plated contacts should work far better on all fronts, from not corroding to having less resistance which prevents a host of other issues :)!!

    If I may ask, what connector is that for?
     
  16. fatbillybob

    fatbillybob Two Time F1 World Champ
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    Dave,

    Why is it that I don't seem to see this problem Bosch connectors on BMW's? Once having a spirited discussion with a guy at bosch I accused them of selling the "seconds" to Ferrari. They adamantly claimed that Bosch had no seconds. They either meet spec or are trashed. Well somehow I swear all the trashed connectors always seem to end up on Ferraris. I'll open up a 5 year old connector on a BMW and there is not dirt and whatever greasy crap they put in there still looks factory fresh.
     
  17. No Doubt

    No Doubt Seven Time F1 World Champ

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    Like BMW and Bosch, Porsche is German...but I've seen the bad connectors up close and personal on Porsche 928s. Maybe the problem is exacerbated by extreme engine temps...the Ferrari 355 certainly qualifies there! Surely at least *some* of the rubber boot cover deterioration is heat related.
     
  18. davehelms

    davehelms F1 Rookie

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    #43 davehelms, Jan 29, 2009
    Last edited: Jan 29, 2009
    FBB / ND, I have no clue.

    The rubber boots that Ferrari used were failing when the cars were under warranty, that I remember. I can recall pulling a 550 intake to do the coolant hose a few weeks after the car was delivered new and do remember the injector plug boots already coming apart. As the 550 is not a terrible hot running beast, the cats are tucked down low and behind the injectors with the radiator airflow going the right direction to help the cause and not hinder it.... I think it was just crappy material used and I would bet the Germans were not involved in any way with that.

    I have always stated that when the engineers at Ferrari got done drawing something up, it was damned good.... right up until the production team started Redlining the drawings and factoring in a profit margin and I suspect a degree of planned obsolescence.... I suspect this is the point where consumer acceptable met up with genius. After we pumped enough Grappa into the training director at the factory one evening (a new hire at Ferrari and directly from Bosch in Germany) we learned in depth the level of politics in play within that relationship in years past. You only have to picture a chiseled jaw Germany being preached to by a flamboyant, hot blooded Italian while discussing how Bosch WILL build a system for Ferrari. I too woke up the next morning with a splitting headache but I do remember quite well that was the image I came away with while listening to our Factory Training Director. The question was asked of him "why did the 348's have such a difficult time with the CEL's" and at that point he only smiled.... You draw your own conclusions.

    I have many hundreds of connectors I have ordered in over the last year and now know that they without question, are not all created equal even within the same product design lines. It got to the point where I would open a package, inspect what was sent, make notes in my file of what I received and throw it directly in the waste basket because I had so many different variations, many no better than what I was replacing, it was getting hard to keep track of it. The obvious was consistent in that each design drawing with the parts spec's showed the Gold plating to raise all of the conductivity, cycle life and to a lesser concern the current capacity readings by huge margins. I almost gave up at one point and lowered my expectations to using silver plating where the spec's were bettered by a factor of 5 over the OEM material but then I would have no visual indication of which were replaced and which were the OEM tin...not to mention that I would have been leaving a LOT on the table as the spec's raise another 500% between Silver and Gold.

    The boots I choose are the only long term concern I have in this kit. There is no way for me to project how long they will last unless I did extensive environmental testing...... As it sits I will not see a payback if every car in the USA gets the kit installed, I had to draw the line somewhere. I choose these boots (I have boots from every Euro, Domestic and aftermarket manufacturer I ordered in before choosing these) as they are very thick and have a long neck that seals on the harness sheath with a great deal of pressure. As some of the harness sheath I have run across is getting quite stiff over the years and the plastic conduit that the 348 and other models use is terribly stiff, I wanted a boot that would exert a great deal of pressure in this area and at the plug to assure a good seal. Right or wrong, this is the reason I choose them and in some areas they cannot be used due to their bulk and I have other boots that are required for these. I had some boots that visually appeared correct next to the OEM accordion types but they simply did not exert enough pressure on the plug or the sheath to make me comfortable and my first goal was function, not appearance. I also had to draw the line and decide that I would only supply the 2 and 3 position boots in the kit as vast majority of the larger ones I ran across were still serviceable. I stock a few of the larger boots but the kit cost was a concern and again I had to stop somewhere. Only time will be the test with these boots BUT the country of origin was Germany which has to be a little bit assuring. As I still have dozens of different boots still on back order that I will be getting over time I would bet the kit will evolve as more user friendly products are identified in this area. I even ran this past my hose engineers but I already have enough molding costs with them doing the fuel system components....I decided I did not want a custom line of FI boots as well!

    This whole project was stalled at two cars done (Niki resigned twice while doing one FChater's 94 with the engine out, if I recall she even gave her notice to the owner when he was at the shop doing some detail work) until the boot installation tool I designed proved itself functional. None of this was any good unless the job could be justified regarding the end cost to have it done. Two days to do a car PROPERLY with the engine out without it with a great deal of trauma to the harness and boot and now less than 1/2 that time to do the job PROPERLY with the engine in with the tools....less yet with it out. Simple, but effective and functional.
     
  19. No Doubt

    No Doubt Seven Time F1 World Champ

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    I love special tools!
     
  20. rivee

    rivee F1 Rookie

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    Ditto here. That's why I make my own, so I can play with them anytime I want.
     
  21. fatbillybob

    fatbillybob Two Time F1 World Champ
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    The service you do for the 348/355 owner is unparalleled. Just as a datapoint in my own 348 ownership situation I had so many electrical problems to a once perfectly running 348 that after years of ownership the OEM electronics gets worse and worse. The reason is degradation with age and all the on/off cycles that you mention that I never even thought about. I was at the point of selling the car to escape the pain. Then I discovered the racetrack. The track was an obvious place where lighter and simpler was better so a 348 race car was born that evolved into almost no OEM electronics. The ghost of lucus took on final stab at me with an on track electrical fire. That ment war and eveything that did not make the engine run was removed. I even ditched the OE key switch for a start button. At that point the 348 became a flawless running vehicle and never failed me. I swear it even felt more powerful. I say if you want a good running car you either have to gut out all the wires and build a racecar or do a "Dave Helms conversion" to keep it stock. There is no question that these cars need revamped electronics.

    Dave... do something in manufacture to make your harness easy for the rookie to pick out during his PPI. Cars in the future resold with the "Helms harness" will bring a value added premium at resale.
     
  22. f355spider

    f355spider F1 World Champ
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    #47 f355spider, Jan 29, 2009
    Last edited: Jan 29, 2009
    He did, and mentioned in the post above. The pins are gold plated, not tin. Compare the photos he posted in this thread (go back to page 2, post #38 http://www.ferrarichat.com/forum/showpost.php?p=138374778&postcount=38). :)
     
  23. saw1998

    saw1998 F1 Veteran

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    Dave, when I grow-up I want to be you.
     
  24. davehelms

    davehelms F1 Rookie

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    Removing a plug would be one way.

    As it is my intent to keep everything I am doing very discreet regarding any labeling, I suppose a small Printed shrink tube piece could be included to install on the cam sensor wiring to identify the upgrade. I am not opposed to something so long as it is small and discreet.

    Suggestions?
     
  25. f355spider

    f355spider F1 World Champ
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    #50 f355spider, Jan 29, 2009
    Last edited by a moderator: Sep 7, 2017
    I guess I should explain how I was selected to become the "beta tester" for this project. As some of you may already know, my car has had a troublesome cold starting idle issue for about 3 years. It has been looked at by the local dealer on several occaisions, but due to it's intermittent nature (this would only happen on every 2nd or 3nd cold start, and only cold starting), they have been unable to diagnose the issue. What would happen, is you start it, and it immediately fires up, and cold idle is 1400rpm or there about...but within seconds it drops to 750rpm and stumbles. If you shut down and restart, it almost always restarts correctly at 1400rpm. Sometimes it takes a third try. Car otherwise drives and runs perfectly. I cleaned and treated all connectors with CRC electrical contact cleaner and Stabilant 22a, no change. Dealer cleaned idle control motor, no change. I replaced idle control motor, no change. I tested, then later replaced throttle position sensor (seemed okay), no change. I then recleaned and treated connectors, including plug to Motronic and fuses and relays to Motronic and fuel pump, no change. Took back to dealer, who replaced pins on connector to idle control valve (said one looked bad under inspection), but no change. During major service, dealer replaced all connector boots, and reinspected all pins. No change. I replaced water temp sensor to Motronic, no change. Took back to dealer to test fuel pressures, all okay, left connected for several days, under cold starts, all pressures perfect.

    At this point, I felt pretty dumb founded as to what to do next. Dealer, in their defense, was having difficulty replicating the problem, though it occurred for me on every 2nd or 3rd cold start, regardless of season, summer, winter. It got to the point, that the service manager said he would even come to my house and have me fire it up in front of him to witness the problem and attempt to diagnose, but I felt bad to have him come and it won't do it...so for the time being I declined.

    Dave Helms contacted me about his suspicion that this may be a connector related issue. Of course I immediately said "impossible" as I had cleaned and treated my connectors repeatedly and they were inspected only last year by the dealer when the boots were replaced. But as Dave went into detail on the problems and issues with the connectors, and how hard it is to clean, and even inspect the connectors, I came around to the idea, that maybe this might help. It certainly could not hurt.

    After many weeks and months of discussion, emails and updates (Dave was working hard to source the best parts, and at a reasonable cost as well), the kit was delivered to me about two weeks ago. I finally got started on the project last Friday night, January 23rd. Took me 5 hours to repair every connector on the rear of the engine, including both plugs to the coils. The only plugs I have left to do are the fuel injectors, crank sensor, water temp sensor to the gauge, and the two solenoid valves that operate the exhaust bypass valve. Dave's instructions where very detailed on how and why I needed to clean each plastic housing once the pins were removed, and to thoroughly clean the freshly stripped wire with contact cleaner and a ss brush (repeatedly), before crimping the new gold plated connector on. Due to the torn boots, the wire at the crimp gets corrosion from moisture, and this moisture actually creeps up under the insulation jacket. I noticed on some of my splices that the wire did look a bit tarnished, but regardless, all wires got the full cleaning treatment. Dave sent me photos of some wires he stripped that were literally black with corrosion...under the insulating jacket! The next step is to thoroughly clean the male pins on the receiving connector, with lots of brushing and flushing with contact cleaner. Basically everything is being renewed to "better than new" with this process. And the new boots will ensure this work stays this way for a long time.

    With the connectors I have so far replaced, which include the idle control motor, water temp sensor to Motronic, and throttle position sensor, these are key to signalling the Motronic the car is "cold", "at idle" and controling the idle itself. I have since started the car after letting it sit for at least 12 hours or more in my cold garage (7 times now) and every start and cold idle is PERFECT!

    Upon inspection of the removed pins with my 8X loupe, I could see that most all the pins were dirty, in spite of my cleaning efforts (they are buried in the plastic housing) and had Stabilant 22 residue on them...a yellow jelly looking goop. Some of the plastic housings still had some what appeared to be traces of dielectric grease too, which I scrubbed out. There is great variance between the individual pins in how much tension they had. Using a business card, some would grab snuggly, others less so, a couple could not grab at all, and fell off! Of course Dave's new gold plated ones all grabbed very tightly. Not sure if they are spec'd differently or just because they are new.

    All in all, this corrected what was obviously an intermittent connection issue, that was not easily diagnosed. But most imporantly, this is going to prevent future issues that were likely to crop up.

    My thought is anyone that has cracked connector boots, you will have issues, even if you replaced the boots. Replacing the boots is preventing further damage, but trust me, there are issues already with corrosion, and connector tension. If you have a car more than 6 or7 years old, you can probably also benefit, simply from renewing your old pins, that are losing tension, and also you can preventively replace your boots before they start all failing. This will certainly keep the electrical "gremlins" at bay. ;)

    I know there are going to be guys trying to figure out a way to save a few bucks and source parts and tools themselves. I did a bunch of checking, and seriously, you cannot get these gold plated connectors at anywhere near a decent price unless you buy thousands of them like Dave did. Same with his boots. Eagle Day sells a decent enough boot (that is what the dealer installed on my car and I left them on) but Dave sourced better ones from Europe. I have some samples, and they are thicker at each end, and fit tighter to the plastic housing and wire bundle. Same with the tools, I was going to use my own, but when I got my hands on these, I told Dave "SOLD" I am buying these, and not returning them...they make the job so much easier to accomplish. The wire stripper is really slick, and the crimper allows you to accomplish the "double crimp" the connector requires in one step, not two...which to me, means half as many chances to F it up. ;) The extractor tool works well too, with a minimum of fuss. I have heard from others that some extractor tools simply do not work properly, you end up forcing the pins out.
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