Running issues with '88 Testarossa. | Page 3 | FerrariChat

Running issues with '88 Testarossa.

Discussion in 'Boxers/TR/M' started by uzz32soarer, Jan 2, 2008.

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  1. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
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    Robert Hayden
    Jeff it didn't matter how much I turned them I couldn't get the idle mixtures down below 15.8. Any more and it just wouldn't run. I kept trying to balance the air by pass screw (big brass one) and the mixture adjusters but even with the RPM held up by the air by pass screws I couldn't get the AFR's down. I would have loved to see 14.7 at idle, or even slightly leaner at 15's, but it wasn't possible. I figured I would even go stupid rich at idle like 13's, just to try and richen up the cruise and just see if the lurching went away, but it wasn't possible to get that range of adjustment out of the old girl.
     
  2. uzz32soarer

    uzz32soarer F1 Rookie

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    I just had a chat on the phone with a fellow F Chatter and TR owner in Sydney with a 91TR running KE Jet. He has a similar issue on very light running throttle at the exact same rev ranges as I do. His problem is nowhere near as emphaasised as mine as he can throttle down and drive through the glitch, but after looking through his entire electrical / ignition system, he is convinced that his issue lays in the fuel delivery. He replaced his injectors and for six months it was like finding another 50 hp, but then things went downhill again.

    His car is a UK delivered 1991 model so I think that it is probably the same as mine and has no O2 sensor.
     
  3. carguy

    carguy F1 Rookie

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    Yes it's a good idea to replace the old steel injectors with the new brass ones - and eliminate any issues due to corrosion.

    I have a hard time grasping the idea the no matter how much you turned the mixture screws that the AFR would now go below 15.8. It still seems as if there is some "unmetered" air entering somewhere. Here's some stupid questions and don't shoot me for being obvious, but when you are adjusting the mixture screws, are you plugging up the access hole prior to measure the AFR? Does pinching off the aux. air valve hoses cause a change in idle speed (with the engine warmed up)? If you screw in the idle air bypass screws far enough...will the engine die?

    We have just gotta to figure this thing out.....
     
  4. uzz32soarer

    uzz32soarer F1 Rookie

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    eYEs Jeff, we were re covering the holes above the mixture screws before taking the readings and also the car would die if the air by pass screws were turned to far in. I didn't check pinching the aux air valve hoses. I can do that pretty easy whilst it's apart.

    How much idle vacuum should there be at the brake booster? That's the longest vacuum run isn't it. I should hook up a vacuum guage and see what I have at all the vacuum points.

    Just have to figure out where they all are and what I should have at them.
     
  5. carguy

    carguy F1 Rookie

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    Robert, you can hook a vacuum gage up to the ports at the rears of the intake plenums, the ones with the hoses that go to the fuel evaporative cannisters. The main thing is to get a balance between the two banks. A good rule of thumb for a starting point for the idle air bypass screws, is to screw them all the way in (don't ham-fist them tight...just till they bottom out) and then back them about about 1.25 to 1.5 turns, and procede from there.
     
  6. fastradio

    fastradio F1 Rookie
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    Robert,

    Sorry to jump in so late here, as I just saw this thread...I spent many years in my early automotive daysdoing in-shop diagnostic semminars for Bosch on CIS, CIS-Lambda and CIS-E. Although my skills are a bit rusty from lack of recent exposure to these systems, here are some things to consider.

    Going back to basics and what I think I know thus far from your posts:

    1) AFR lean: Go no further-> Disconnect the brake booster hose per Jim's comments and re-check. A leaking booster can create a massive vacuum leak that cannot be compensated for.

    2) If the booster is not leaking, consider using a propane ienrichment/injection system to "sniff" for vacuum leaks. If the idle speed rises, or your AFR improves, you've got a vacuum leak.

    3) Disable/plug off your Aux. Air Valve circuit. This system, if allowing air to pass when the vehicle is "warmed up" will send you down the wrong road.

    4) Check that the throttle plates are indeed set correctly. They should be open no more than .003-.004" with a wire gage.

    5) In that the system does not have a WUR per se, you must know if the temperature sender is working correctly. This really sets the EVA current curve.

    6) Voltages and grounds: Often overlooked, all electical systems must be at the same "ground plane."
    -Measure the voltage between the battery negative post and chassis. It should be 0.00 Volts on the millivolt scale.
    -Measure the voltage between the chassis and the base of the coolant sensor. It should be 0.00 Volts on the millivolt scale.
    -Measure the voltage between the chassis and the fuel distributor. It should be 0.00 Volts on the millivolt scale.
    -Measure the voltage between the chassis and the ECU ground pin. It should be 0.00 Volts on the millivolt scale.

    7) Is the alternator output above 13.2 Volts and "clean". Is the output clean? (Just because the "alt" warning light isn't on doesn't mean all is "OK".) A scope will confirm...

    8) What is the voltage at the ECU? It should be the same at the battery voltage under all conditions.

    9) Have you look at the HC levels on an exhaust gas analyzer? I have chased my tail, more than once, only to find that the "car won't run right" because of a bad wire (that only shows up under certain temperature/load conditions).

    10) Put a timing light on her. You need to know with 100% certainty if she's advancing, or not. If not, is it a bad spark box, or a vacauum leak to the box?

    11) I presume that fuel pressure and volume was verified...

    Hope this helps a bit...

    Regards,
    David
     
  7. uzz32soarer

    uzz32soarer F1 Rookie

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    #57 uzz32soarer, Jun 11, 2008
    Last edited by a moderator: Sep 7, 2017
    Wow, thanks David.

    There's a bunch more things I can check.

    Firstly, if I had a vacuum leak that was substantial enough to cause this leanness, wouldn't the car run badly at idle where vacuum is quite high? I've always known cars to run really lumpy when they have big vacuum leaks?

    So I should trace the brake booster hose from where it leaves the engine and blank that pipe off right?

    A propane enrichment/injection system to 'sniff' for vacuum leaks. You have me lost on that one. In the past I have sprayed carby cleaner along a V8 inlet manifold looking for leaks. If the revs changed then I knew it was sucking in a little of the carby cleaner. Is this what you mean? Should I compare vacuum at various points on both manifolds to see whether there is any differences side to side.

    I take it that the auxillary air valve circuit is for cold running. Therefore if I just remove it and connect a single hose from point to point, is this correct or does it work the other way and close off as it gets warm, so therefore I would have to close off both sides once it's removed.

    Throttle plates? 0.003 - 0.004 thou clearance around the butterfly flap or where? Just need a hand here as I'm not a mechanic, just a bloke! I need to be led by the hand a bit, sorry.

    WUR I'm not sure on either. But I am concerned about the temp sensor. As the car warms up, what sort of readings should the temp sensor give out. If the temp sensor is telling the ECU that the car is too hot, this could lean off the fuel I expect so I would like to check the correct operation of the water temp sensor somehow.

    Voltages and grounds - easy - I'll check all those tomorrow.

    HC levels haven't been checked. It wasn't a four way gas that was used, just a lambda wide band probe and analyser.

    Where do you check timing on these old girls when the belts and balancer are at the front of the engine? What should the timing be anyway?

    Checking fuel pressures and volumes on the weekend as per Steve's last post above. Have to source some of those scientific graduated skinny beakers from somewhere.

    I've decided also to change out the injectors. This car has done 21000 miles in the UK and a further 12000kms since I've had it home in Oz. I'ts had fuel filters about 8000kms ago when FF tuned it here in Melbourne, but the injectors are still originals and manifolds etc have never been removed as they still have all the factory paint markings on them.

    I figure that I have leanness right accross both baanks, but only under specific conditions ie: 2500 - 3200 rpm at very light throttle opening and near zero load (flat road) so I'm wondering if my injectors are flowing enough. I figured for the small cost I might as well change them all out and stick in a new set of brass ones anyway, so tonight I stripped down everything ready to lift out the injectors tomorrow.

    So here's where I'm at tonight. Is there anything else I should look for whilst I have it down this far?
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  8. fastradio

    fastradio F1 Rookie
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    My best advise is the "eyes wide open" method of diagnostics. I have been "stumped" many times by overlooking the most simple of things...and the "KISS" (keep it simple stupid) system, when I remember to use it, usually finds the problem.

    Best of luck...This will be an exciting issue to resolve.

    Regards,
    David
     
  9. uzz32soarer

    uzz32soarer F1 Rookie

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  10. uzz32soarer

    uzz32soarer F1 Rookie

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    #60 uzz32soarer, Jun 12, 2008
    Last edited: Jun 12, 2008
    I've located a KE specialist in Australia, but he's in Tasmania so he's a long way away.

    I wrote to him of the problems and all of the tests that I've done and this was his reply:

    You need to disconnect the electro hydraulic acctuators from the fuel distributors, run the engine to operating tempreture, set the idle mixture to 1.5% CO and go for a drive. If the problem is still there I would say it is probably not the KE system causing it. If it is suddenly much better it is either the electronic control of the KE or the fact that the base mixture was not set correctly. It is a waist of time trying to set the mixture with the EHA units connected as the ECU will just keep changing the mixture to where it thinks it should be.

    Now once I figure out where these actuators are I'll follow his advice and have a go. BTW, does 1.5% CO mean the same as 14.7 AFR, as I don't have a four way to set the CO levels.

    (I'm perplexed a bit by this new info. Pulling the plugs on the EHA units is okay, but this car has no O2 sensor, so what will tell the ECU how much fuel the car needs?)
     
  11. fastradio

    fastradio F1 Rookie
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    #61 fastradio, Jun 12, 2008
    Last edited by a moderator: Sep 7, 2017
    Robert,

    Does you car utilize frequency valves and oxygen sensors?

    If the the answer is "Yes", then what your specialist makes sense. The "base" mixture must always be set "open" loop first, meaning that the oxygen sensors, frequency valves and lambda control boxes are out of the loop. If the base mixture can be set "correctly", the lambda system will maintain the mixture level within a very tight range. (To set the base mixture levels, simply unplug the oxygen sensors.)

    However, if your car doesn't have these components, his input does not apply to your car.

    Here's a chart of AFR versus CO for your use.
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  12. uzz32soarer

    uzz32soarer F1 Rookie

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    I don't know what frequency valves are, but it has no O2 sensors. It's a 1988 UK spek KE JEtronic with no O2 sensors.
     
  13. fastradio

    fastradio F1 Rookie
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    Robert,

    Sorry...I got KE and K confused for a moment. No frequency valves are used on a KE system.

    Re-reading your previous post; Since you do not have O2 sensors, your system always runs "open loop", meaning that there is no emissions based feedback system to pull the mixture back to a pre-defined setting. Once you set the base mixture, it should maintain that base value.

    So, unless I'm missing something, or just can't recall, I don't see how disconnecting the "valves" he refers to will make any difference, as now the ECU has no basis at all to set mixture, based on engine temp, etc.

    Regards,
    David
     
  14. uzz32soarer

    uzz32soarer F1 Rookie

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    I think it's a test.

    Pull the valves and set the mixtures rich. Then drive it in a fixed mixture position, a bit on the rich side and see if my jerking issue goes away. If it does, then it proves that it has something to do with the KE Jet system. If not, then look elsewhere, like fuel pressures, ignition etc.

    That's my interpretation anyway. Do you think that makes sence?
     
  15. fastradio

    fastradio F1 Rookie
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    I can't say I recall doing that test on a KE car. However, if she does run fine in the mode described, that would tend to say that there's a problem with the KE-system controling the mixture. I think this makes sense. (1.5% CO isn't really that rich anyhow...It certainly won't do any harm test purposes.)

    Regards,
    David
     
  16. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
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    Yes, that's the Suggestor's intention -- to operate your system in a quasi-K-Jet without Lambda way which will give a rough test of the fuel delivery from the mechanical/hydraulic parts of the system (at the single temperature where you've manually retweaked it to be OK at idle with EHA current = 0 mA).

    1.5% CO might be a little less (i.e., more rich) than 14.7:1, but not a lot.
     
  17. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
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    You've got the right thought here -- there are fewer "inputs" on your KE system than a US version KE system, but it still uses things like the signals from the airflow potentiometers to provide enrichment (by increasing the EHA current briefly) during quick throttle opening, etc.. He's more suggesting a test where you would set things up at warm idle and then increase RPM slowly and see if it's improved/not improved/still flat at a particular spot/etc..
     
  18. uzz32soarer

    uzz32soarer F1 Rookie

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    #68 uzz32soarer, Jun 13, 2008
    Last edited by a moderator: Sep 7, 2017
    Well today was a very long and interesting day!

    I started to changed out the injectors this morning with a borrowed tool that pulls the injector out leaving the collet in place and no engine disasembly required. I took the first one out and it was very obvious that hese had been in there for 19 years. The bottom O ring on the collet (little one) was destroyed, and there was carbon build up on the underside of the fat O ring that holds in the injector. Bad start!

    So then I needed to pull all the collets out. This required removal of the lower section of the intake manifolds which sounds pretty easy, until you start to do it. The rear two come off just fine, but to get the front two off, you need to remove the water spout, and to remove that you need to remove the entire injection system. Great!

    That started a rather hellish day. Once I got the injection system out of the way, and very carefully bled the water out of the system so it didn't saturate the carpet in my garage, I could then see the two front lower manifolds and see how damaged they were. Corroded, paint flaking, just plain ugly. And the mess on the engine block. My car has always been pretty clean, and obviously the previous owner only cleaned what could be seen. The car still had paint lines on every nut and bolt from the factory, so has obviously never been apart at the top. There was no way that I could put new shiny injectors into those crap lower manifolds, and then put them back onto a filthy engine.

    Bugga!!

    Ten hours later it's in paint and drying. First a degreaser and stiff brush. Then clean off that mess and dry with a suitable cloth and air compressor. Then get out the die grinder with an assortment of wire brushes and get into it after plugging up all the holes and covering the water hole particularly. After many hours I washed it all down with white spirit, masked it all up, and then sprayed on a VHT base primer, followed by multiple coats of VHT aluminium engine enamel.

    Meanwhile, between coats I sandblasted and prepared all of the manifold parts, both upper and lower sections and treated them to a primer, base coat, and then a VHT wrinkle finish, followed by a super light mist of the engine enamel so that the colours matched.

    Into the wife's oven for curing and the wrinkle came up beautifully. Then the same treatment to the upper manifolds, followed by the wrinkle red late tonight, then into the oven with that too. Good thing I had the foresight to buy her the big 900mm wide oven a few years back. Comes in mighty handy!

    So, that lot is all drying overnight and I've just come up after 14 hours in the shed today. Winter has set in, so I've burned about 100 kilos of wood in the pot belly stove today to keep the shed temp up enough to paint. It's 4 degrees C outside, but 21 in the shed. Hahahah. T shirt weather.

    I purchased a sheet of 1mm gasket material and traced the only two gaskets I managed to get off in one piece from the bottom of the manifolds, and the wife got out the hole punch set and hobby knives and cut a full new set of gaskets for me before she cooked the dinner so they are ready to go.

    So tomorrow, I'll head out early and try and find a suitable product to assist me in getting the injectors mounted into the collets, a few litres of cleaning fluid to wash everything down and a bunch of new stainless cap nuts as they were mostly rusted. Might as well change them all too, now that it's all shiny.

    So hopefully she likes the attention and when the new injectors go in, she behaves herself. I live in hope!!

    Here's some pics of the days dramas, including my method for injector / collet removal if they are stuck in the lower manifolds which 11 out of 12 of mine were. Remove the circlip with a cloth over the top to catch the clip as it leaps out, or you will be on hands and knees on the shed florr looking for the little suckers.

    Once all the clips are out, grab a 10mm deep set socket and turn over the manifold so you are looking at the base of the injector sticking through. Slip the deep set socket over the top and using a suitable pin punch, belt the socket with a hammer. The tip of the 10mm socket is a perfect fit on the base of the collet and the socket will pass right through the collet hole. I use a 1/4 drive socket. Best way I've found to remove them with no damage to any part.
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  19. carguy

    carguy F1 Rookie

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    Great Job there Robert!! Those pictures sure bring back memories. If I may ask, what type and color of crinkle paint did you use on the intake manifolds and tubes?
     
  20. uzz32soarer

    uzz32soarer F1 Rookie

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    Well another 14 hour day and she's all back together and running. Phew!

    Certailnly richer, but still not right. Numbers: Idle 15.4 Cruise: 17.8 WOT: 13.5

    So still very lean on cruise and it still plays up around 2700 rpm at cruise. If we could say **** here I would!

    Anyway, the engine is all clean and painted, new injectors, new seals and O rings on injectors and collets. That's got to be good for the old girl anyway. I'll post some images of the rebuild tomorrow. Bit knackered now I must admit.

    Jeff, The paint used was VHT which I think is an American product. www.vhtpaint.com or www.pj1.com and click on VHT.

    For the block I used Hight Tempreature Prime Coat light grey primer Product Number SP-304. For the engine top coat I used Very High Temperature Engine Enamel in colour 'Universal Aluminium SP-127. For the wrinkle on the manifolds I used VHT Wrinkle Plus coating. SP-205 Grey. Once the wrinkle dries to touch, you have to put the lightest mist of the engine enamel aluminium over the top of the wrinkle. Just mist it, dont let it build up at all or you will lose the wrinkle. This is the only way I've figured out to match the colours nicely between the engine paint and the wrinkle.

    Got to fall into a long scotch and dry about now.
     
  21. uzz32soarer

    uzz32soarer F1 Rookie

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    Update time:

    The new injectors, O rings and seals have made the car feel wonderful. Best it's ever driven, but still not right!

    I have fitted O2 sensor bungs into my Bell exhaust so now I can read each bank perfectly as they were crossing over inside the muffler and making it near impossible to tune AFR's. Now I can just screw a wide band O2 meter in on each side and set them up perfectly and individually.

    So leaving everything connected, I set AFR's to 15.1 at idle and went for a drive. Car is much crisper, has much more power and a totally different sound, especially off the line. More grunty, hard to describe. But the cruise AFR's are still around 18.5.

    So going back to the info supplied by the Tasmanian specialist, I removed the plugs from the electro hydraulic acctuators (EHA's) at the front of the fuel distribution heads. The car ran terrible, instantly going lean to +30's. So I reset the mixtures as instructed back to low 14's and tried to drive it with the EHA's still disconnected. The instant the throttle was used, AFR's went to low 30's and the car won't even free rev to 3000. I couldn't even get it out of the garage!

    So I ring Tasmania. The guy (Robin Day) is perplexed. He informs me that the car should actually drive perfectly well with the two ECU's completely unplugged and that he wanted to test AFR's with the EHA unplugged to verify that cruise AFR's were in the same range as the idles that I had set without any computer intervention.

    So he's gone off to deliberate for the evening, but I'm left thinking. The plot thickens but I feel I'm getting somewhere and there are certainly gains at every step lately.

    What would cause instant leanness when no ECU signals are being recieved by the EHA's? No fuel or little fuel pressures!!!

    What if I have low fuel pressures and the ECU's are trying their hardest to provide some enrichment but fighting a losing battle because there simply isn't enough fuel delivery? If they were working to provide maximum enrichment, this could explain why I get 18 - 19 ish AFR's with the EHA connected, and stupid lean without the ECU intervention?

    Why would I have low fuel pressures?

    -Dirty fuel in tanks.
    -Dirty filters (I replaced them 6 months ago)
    -Low voltage to fuel pumps? This is possible as my fuse board wires to the fuel pumps were cactus and I fixed this last year. What if I still had resistance in the wires to the fuel pumps and were getting low voltage there. That might explain low fuel pressures?


    So tomorrow I move on to the fuel delivery system but need some answers and gudance first. Where are the fuel pumps? Is there any relay between the fuse board and the fuel pumps? What fuel pressure should I have at the inlet to the presure regulator and then at the outlet of the presure regulator?

    Then the last step will be to check for fuel pressure exiting the top of the distribution heads to the fuel injector lines. What pressure should I have here?

    Also, should I drain the tanks and chack the fuel for dirty deposits? If so, where are the drain plugs located?

    So many question, so little time.

    I've taken annual leave until I fix this thing. The Mrs. isn't impressed but I've told her that I won't be so grumpy once I sort out this issue.
     
  22. fastradio

    fastradio F1 Rookie
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    Robert,

    Most interesing findings...

    Have you:
    -Checked to fuel pump (system pressure) at the fuel distributors?
    -Checked the fuel pump volumes? (cc/minute)

    Without both pressure and volume in specs and known, you're kind of chasing your tail, so to speak...

    Prior to any CIS, CIS-E or CIS w/Lambda diagnostics, fuel pressure and volume is always a good place to start.

    Regards,
    David
     
  23. uzz32soarer

    uzz32soarer F1 Rookie

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    Thanks David, those are on my tomorrow list. Refering back to my post above, I don't know where the fuel pumps are or what the output pressure should be. I think I need to check fuel pressures on entry to the pressure regulator and exit so I can be assured that the presure regs are both working properly but also don't know what numbers to expect at each point.

    Steve M pointed out a way to check flow to the injectors in cc/min but now that they are all new, I really just need to check flow from the pumps to the heads so if you have an idea of how much volume should flow in a specific time, that would be great also.

    So it's numbers that are needed tonight, so if any of you USA guys can assist whilst I'm sleeping, tomorrow morning I'll get into it and start checking some of the readings out.

    Getting excited now. I'm finding problems and problems can be fixed. Just a bit more diagnosing to go.

    Thanks heaps for the halp all you blokes. This car is going to be a screamer...............again............like it once was, and like I've actually never experienced. I thought it was good before, but now it's going to be great!
     
  24. carguy

    carguy F1 Rookie

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    Hope your sleeping soundly Robert! The fuel tanks are located just ahead of - and below - the engine bay. The tanks have a rough texture and are a dull silver in color. The fuel pumps are located in between the two fuel tanks, at the bottom. You will have to remove the fuel pump protection plates to gain access. Once your under the car, you will see where everything is. As for fuel pressure you should have, I think......around 80psi at delivery.

    You mentioned that perhaps the ECUs are fighting a losing battle to provide enrichment due to low fuel delivery...I think this may be correct - but - I have a hunch your fuel pumps and delivery pressures are okay. The Bosch system richens or leans the fuel mixture by the use of valves inside the fuel distributors, based on signals from various sensors and the like. When I'm adjusting my TR fuel mixtures, I first have to establish a "base line" air fuel ratio - with the O2 sensors disconnected - this way there is no electronic "nanny" trying to compensate. Then when I have everything set, I hook the O2s back up and all is fine. There is a way to measure the duty cycle of the fuel system adjustments and verify that things are working right, but I can't remember off hand how to do it.

    For your car (with no O2 sensors), I would try and set the base-line fuel mixtures with the EHAs disconnected, then hook them up and see how the car runs. The fuel system should be able to adjust the mixture both ways - rich and lean - off of the base-line setting. If your system is always attempting to richen things up as best it can - I think your earlier hyposthesis may be correct.
     
  25. uzz32soarer

    uzz32soarer F1 Rookie

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    She's got me spending 'quality time' with her watching the TV Jeff. I'd rather be in the shed fixing the old girl!

    10.07pm here.

    Robin Day in Tasmania (www.southportfuelinjection.com) was really suprised that the car wouldn't even free rev, let alone drive, when I set the mixtures with the EHA units disconnected. He reckons the car should drive fine with no computer intervention at all, and that in reality, the ECU's just do a bit of fine tuning to the mixtures depending on the signals recieved from the other sensors, and in your case, from the O2 sensors. It's baffled him that the car is so crook with idle mixtures set with EHA's off, and why it goes off the scale lean (like 35plus) as soon as the throttle is touched. I literally couldn't get it out of the shed.

    He told me that you can actually unplu the ECU's on a KE Jet system and the car will take you home with little or no fuss on base settings, maybe a little down on grunt but you will get home. That's what he wanted me to do today. Drive the car with EHA's off and base mixtures set, then drive it and report back to him what the AFR readings were at WOT and cruise. Unfortunately, I couldn't do it as it wouldn't drive on off idle AFR's over 35.

    I must be getting somewhere as the car feels great with the new injectors, or maybe she just likes the attention!!

    Haven't heard from Steve for a while. I thought he may have the fuel presure numbers that I need? Maybe he's away somewhere.
     

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