Running issues with '88 Testarossa. | Page 4 | FerrariChat

Running issues with '88 Testarossa.

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

This site may earn a commission from merchant affiliate links, including eBay, Amazon, Skimlinks, and others.

  1. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    Jeff, have you ever heard of anyone having low voltage at the fuel pumps after having burnt pins or tracks on their fuse boards?

    I wonder if the wire goes direct from the fuel pump relay to the fuel pumps or if it has joiners or anything along the way. You know, if that wire builds up age resistance enough to cause the pins and tracks in the circuit board to be burnt, is it feasable to consider that the wire may not be conducting sufficient current to the fuel pumps. Not enough current, not enough flow?

    Just a thought as we all seem to have had issues with the white plugs, and in particularly, the fuel pump connections at the fuseboard.
     
  2. carguy

    carguy F1 Rookie

    Oct 30, 2002
    3,402
    Alabama (was Mich.)
    Full Name:
    Jeff
    I dont think there are any "joiners" for the fuel pump wires. For my fuse panel, I simply wired up the fuel pump and cooling fan relays seperately from the mother board. I still use the relays and all, but now there are good spade connectors making contacts instead of the weak factory "pincher" type connectors.

    Do I understand it, that you DID set your fuel mixtures with the EHA's disconnected? So there was no "input" from the brains during the mixture adjustments? Has it been your experience that only VERY small movements of the mixture screws are needed to change the AFR?

    Yes...the EHA's can adjust the mixtures up or down a small amount...about 1.5 to 2.0 on the scale (with 14.7 base-line being ideal). That is why a base-line mixture setting is so crucial. Based on this assumption it just doesn't seem possible to have a mixture vary over such a wide range. This makes me just a bit skeptical about the readings. The only way the engine could go that lean is for a huge amount of extra air (not metered) to be allowed into the intake stream at open throttle, or there is no increase in fuel flow from idle to open throttle. Here's a wierd and perhaps unrelated question...does your car have an air pump located on the left-front of the engine? If not...are there triangular shaped ports on the bottom of the heads, about in the middle (front to back)? If so are these ports blocked off?

    I'm only guessing here...but I'd imagine the inputs to your fuel system brains are based on the timing, rpms, vacuum, temperature, throttle micro-switch, and airflow metering plate movement sensor. Vacuum is important for the ignition brain, and also for the pressure differential switch (located in the right-front corner of the engine bay). Low vacuum tells the brains that the throttles are open and enrichment should occur. Perahps some vacuum-sensitive item isn't getting a signal? I wonder if a vacuum line could be incorrectly routed?
     
  3. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,038
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #78 Steve Magnusson, Jun 19, 2008
    Last edited: Jun 19, 2008
    Robert's car is an F113B TR (KE-Jet without Lambda) so there's no intelligent connection between the exhaust gas O2 content and the current going to the EHAs.

    Unfortunately, this is not true -- even if all of the injectors are working perfectly, this does not guarantee equal flow rates of fuel are exiting the injectors vs the airflow plate position. You seem to have dismissed the results of the (clever IMO) test with the EHAs unplugged (i.e., constant current of 0 mA in the EHAs and the mixture screws manually retweaked at idle to add back the "missing" fuel) -- just replacing the injectors does not "solve" this problem (if present).

    The regulated fuel supply pressure spec is 5.0 - 5.6 bar (you need a TR WSM!)

    The pressure measured here would not be that useful -- the pressure in the lines going to the injectors would just be a quasi-constant value in each line, regardless of engine RPM, if the injector was working properly.
     
  4. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden

    Not sure what you mean here Steve.

    After speaking to the Tassie specialist yesterday I did set the mixtures without the EHA's attached. There was a huge difference and I had to screw down a heap to get them to 15's with EHA off. But when I tried to drive it with them still off, it goes super lean as soon as I touch the throttle and hasn't enuff power to get out of the shed.

    I take it that when this model is tuned, idle mistures are supposed to be set with no EHA attached, and then plug them back in and away you go?

    If that is the case then I have been doing it wrong as I've been setting base settings with the EHA's attached.
     
  5. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,038
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    No, you've been doing it correctly -- if you want to run with the EHAs plugged in, it should be tweaked up while they are plugged in; and, likewise, for the test for running with the EHAs unplugged, it should be tweaked up when they are unplugged.

    The test suggestor's point is that with the EHAs unplugged (and the mixture manually retweaked for good idle), you know for sure that the EHA current isn't changing in some bizarre unexpected way (because it's zero); consequently, the EHA system can't be causing the lean condition problem at higher RPM, and you almost certainly have some type of fuel delivery problem that is somewhere in the strainer-to-pump-to-regulator-to-FD-to-injector food chain.
     
  6. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    Thanks Steve. Well today seemed like a waste of time. I spent hours trying to locate suitable fittings to T piece into the fuel lines and failed. Aussies, too intent on Ford's and Holden's to carry anything European or metric.

    I got under it this morning and checked voltage at the pumps using the pumps own earths. 13.6v with engine running at idle so that seemed okay. I suppose next I need to check amperage at the same place but need four hands for that so will do it on the weekend with the wife on the key.

    To do fuel pressures I've been trying to conect between the accumulator and the fuel filter as it's rght on the rail and easy to get to. I figured I need to take two readings. One with engine running and system in standard form, and then pinch off the return line to the tank and see if the pressure rises. This should show me static fuel pressure and then with the line pinched off I should be able to see if the pressure reg is working properly.

    If this isn't the right place to test, then I'll have to remove the upper manifold again and test elsewhere. Please advise.
     
  7. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    I got an email back from Robin in Tasmania tonight, who says:

    "Never pinch of the return line or you will instantly destroy the insides of both fuel distributors."

    So now I'm in a bit of a quandary. Where do I hook in to get fuel pump pressurew without pulling the manifolds off again, or is this not possible? Obviously I need to check a few things. Fuel pump volume, fuel pump pressure, and fuel pump amperage.

    I think I also need to check the pressure regulators to ensure that they are working properly, but where and how do I hook into them?

    So far every test that I've done, the car passes except one. When I set the idles with no EHA and then try and drive it, it just goes so lean that it won't even move. I was also told today by a local Ferrari gagrage that excess fuel pressure can lead to leanness on these cars. Could this be right?
     
  8. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,038
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #83 Steve Magnusson, Jun 20, 2008
    Last edited by a moderator: Sep 7, 2017
    You really need to get a TR WSM (with the longer chapter D including the US KE-Jet set-up) and read all of chapter D. No need to measure the fuel pump currents yet (and it's much easier to measure them at the relay sockets rather than in the wiring at the pumps) -- if you had a WSM, you'd know that the first two tests are:

    1. measuring the supply regulated pressure, and (if OK)

    2. measuring the volume of fuel returning to the tank during a fixed time when the fuel system is at the regulated supply pressure with the engine off.

    If both those tests are OK, there's no need to look any further at the pumps.

    The attached jpeg shows where you can measure the regulated supply fuel pressure on a KE-Jet FD (this is the kind of information you would see in the cross-section drawing of the KE-Jet FD internal plumbing in the TR WSM). Most Bosch CIS fuel pressure test kits come with the right M10 x 1 (IIRC) fitting to hook into either of those two ports -- shouldn't be expensive -- way less $ than a day of your time ;)
    Image Unavailable, Please Login
    Image Unavailable, Please Login
     
  9. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    Thanks Steve,

    I have a copy of the WSM on CD but it's not very clear in many respects. Certainly doesn't tell me what your post above does.

    Rob.
     
  10. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    Well that was easy when I knew how to do it.

    1 - 6> 5.5 bar at the correct sampling port on the distribution head with engine running. Dropped and held at 2.9 bar when engine off.
    7 - 12> 5.5 bar at the cold start injector port exiting the distribution head with engine running and held at 3.0 bar when engine off.
     
  11. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    #86 uzz32soarer, Jun 20, 2008
    Last edited by a moderator: Sep 7, 2017
    Steve, when I took these pressure readings I only put the gauge straight into the presssure port / cold start port and read the readings straight from there. I notice that your gauge has a T fitting that you probably take to the side of the warm up regulator / control pressure regulator.

    If I T into my system, where would I pickup the control flow from.

    My primary pressure regulator has two inputs, one large hard steel line, and one smaller nylon line, and one return to the tank. As per the image below.
    Image Unavailable, Please Login
     
  12. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    #87 uzz32soarer, Jun 20, 2008
    Last edited by a moderator: Sep 7, 2017
    Even the WSM only talks about the control pressure regulator type of system and gives good notes on where to pick up lines, but this isn't much good in my case.

    The WSM indicates that the connections must be done like this:
    Image Unavailable, Please Login
     
  13. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    As my system is totally different, I have to presume that to ascertain control pressures, that I need to read the presures from the small nylon line that runs from the side of the distribution block down to the side of the pressure regulator - ie: the line missing in my photo above.

    If fuel pressure is removed from this line, I would expect that the pressure regulator closes, and no fuel is returned to the tank thereby giving me a primary system pressure, which should be 5.5 bar or thereabouts. If I then open the valve on my presure gauge and allow fuel pressure to flow along this line, then the pressure regulator should open, dropping system pressures down to about 1.6 bar (20 - 25 psi) and allowing fuel to return to the tank.

    Does this theory sound correct?

    I have K Jetronic and KE Jetronic Bosch Technical Instruction manuals as well as the Ferrari WSM, but this is as clear as mud in all of them.
     
  14. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,038
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #89 Steve Magnusson, Jun 21, 2008
    Last edited by a moderator: Sep 7, 2017
    You are confusing K-Jet (that has a "control pressure" involved) with KE-Jet (that does not). Even though the FDs for each type look very similar, the internal plumbing/construction is completely different -- compare the K-Jet FD cross-section in Fig 8 page D11 to the KE-Jet FD cross-section in Fig 53 page 73.

    The figure of the gauge connections you posted is only for K-Jet systems -- the way you measured (directly at the cold start injector port or the top test port) is correct for KE-Jet (and the values are OK). Does your TR WSM have pages D68-D105, or does it end at page D67?

    Bottom line is that your regulated supply pressure measures OK, and if the fuel delivery test is OK, the next thing to measure is the fuel flow rate out of the injectors themselves (post #45). The fuel delivery test is described on pages D37-D38, but the connections are described for the K-Jet system (where the pressure regulator is part of the FD so the return line shown in Fig 31 page D38 comes from the FD). For a KE-Jet system, the return lines to the tank come from the pressure regulators and are shown in Fig 48 of your OM as labeled here. Remove the rubber line going to the tank from the steel line coming from pressure regulator; connect one end of a new rubber line to the steel line; and put the other end of the rubber line in the measuring container like shown in Fig 31 page D38; jump the fuel pump relay socket and run the fuel pump for 30 sec -- if you get more than 1 liter, all is OK.
    Image Unavailable, Please Login
     
  15. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    No, I haven't got the systems confused Steve, I know what I have and I know that the architecture of the heads is totally different, hence EHA's and no warm up regs etc on my car, and no internal pressure reg but an external one instead that operates differently.

    The thing it, all documentation that I have deals with the earlier system and how to test it and it's quite specific in that you need to know system pressure (75psi) AND controlled pressure (20 - 25psi). Now, I figure this is also important on my system, or else how am I going to know if I'm getting control over the fuel pressure from my pressure regulators?

    There musty be a test for them to see if the actual pressure regulator is working as designed.

    I have done primary pressures as your drawing shows, and so far that looks fine.

    I can get to the return line on the RHS pretty easy to test the return volume to the tank from the pressure reg, but I think I'll have to remove the manifold on the LHS as the oil filer, allow breather pipe, and the alternator cooling duct are all in the way of the steel to rubber pipe join so I'll do that next and report back in with the volumes of the tank return lines.

    This still doesn't tell me that the pressure regs are doing their job properly though.

    So far we know that all electrics appear to be working correctly as per yours and David's tests.
    We know that I have 13.3v at the fuel pumps and that the grounds are good.
    Primary pressure at the fuel heads / cold start injectors is 5.5 bar.

    I also know that if tuned with EHA's attached and idle mixtures set to 15.1 that I have cruise mixtures of 18.5 even after the new injectors have been fitted and WOT just makes it into the 14 range.

    If I tune the idle mixtures with no EHA's to 14's, the car idles fine but wont free rev or even produce enough power to move, and the AFR's go off the scale (40) super lean as soon as the throttle is touched. This is with the EHA's left unplugged as suggested by Robin in Tasmania as his simple test.

    What I don't know yet (and some of these things may not be critical):

    1. If my pressure regulators are working properly.
    2. What my timing is at idle. Can you tel me the figure expected here ie: 10d btdc etc.
    3. Am I getting ignition advance as the revs lift.
    4. What amperage my fuel pumps are drawing under idle and load.
    5. What the flow rate at the injectors is.

    At least it's miserable, raining and freezing cold. I don't mind the car being off the road when it's like this, especially when I feel that we are making progress even though it's a very frustrating diagnostic process.

    Without you, Dave and Jeff, I'd be buggered, so keep the sugestions coming and between us al we can beat this. It's only a machine after all.

    Rob.
     
  16. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    OM says ignition timing at 1000 rpm of 8 deg and advance to 30 deg at 5000 rpm. Doaes anyone have an incremental advance table or tell me what it should advance to at say 3000 rpm. I'm not free reving it to 5000 in the garage in it's current state.
     
  17. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,038
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    I repeat -- there is no control pressure to measure on a KE-Jet -- do you have pages D68 to D105?

    Yes it does -- the only function of the pressure regulators is to keep the supply pressure at the 5.0-5.6 bar value (with adequate flow volume) -- the regulated supply pressure doesn't change with operating conditions/loads.
     
  18. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    No Steve, mine stops at D60 being the last page.

    Page 138 of 557 in the manual.
     
  19. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,038
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #94 Steve Magnusson, Jun 21, 2008
    Last edited: Jun 21, 2008
    I'd recommend that you get them -- even though they are for a US KE-Jet with Lambda, it will help explain things IMO.
     
  20. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    Is there a source for such things.

    I bought my manual on ebay when I got the car, and have bought the Tech Manuals new from Bosch on the KE Jet system. I've noticed that your posted wiring diagrams are really great quality compared to the CD WSM that I have.

    Where does one obtain such things?
     
  21. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,038
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #96 Steve Magnusson, Jun 21, 2008
    Last edited by a moderator: Sep 7, 2017
    I got mine from www.ferraribooks.com, but it's like the F parts -- there's 3-4-5 typical on-line F literature suppliers if you search -- and Maranello Concessionaires had some unbelievably reasonable prices on F literature a few years ago, but that was when they were associated with the Owners Site so maybe not anymore.

    If you'd need to buy the whole WSM to get those pages, and don't want to, another option for you is the special booklet that they did for your "Standard Version" (Versione Base) KE-Jetronic F113B. It's really just a subset of the same US Version KE-Jet information on the D68-D105 pages with the O2 sensor and thermocouple stuff left out so either would do. I have a Mar Parts reprint Part No. 95990856.
    Image Unavailable, Please Login
     
  22. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    Well I didn't get too much done today. Had to take Suzie shopping etc....

    But, I did get fuel pump amperage done. Right: 8.62 amps with relay tripped out, no car running. Left: 8.52 amps. So that looks pretty good, doesn't seem to be too much resistance from the pumps so they appear to be in good shape.

    Also I had a look at the timing. I hooked in to number one spark plug lead, presuming that was the right one?

    AF mark comes up spot on between the pointer bolt holes at idle 1050 rpm. Then A5 comes up pretty much perfect at 5000 rpm so it seems that I am getting the correct advance from the electronic control unit.

    D6 in my WSM shows AF as fixed advance, but on the diagram it shows AF 14 degrees, AA 16 degrees, and A5 30 degrees. The OM shows base timing at 8 degrees, yet with my gun on zero, AF was right on the marker at idle. Is this right?

    I have a timing light that you can adjust the advance knob and one interesting thing, was that at idle, whem I adjusted my gun up to 50 deg advanced, there was a marker on the flex plate that came up. About 1mm deep, 7mm long and 4mm wide. So quite a specific marker and at 50 degrees it was right between the markers. I couldn't find any reference to this mark in the WSM.

    So, anyway, there's another couple of things off the checkout list.

    Seems the last thing is the fuel line return flow test and the individual injector line flow test.
     
  23. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    #98 uzz32soarer, Jun 23, 2008
    Last edited: Jun 23, 2008
    Did this just now, LHS flowed exactly 1.5 litres in 30 seconds. RHS 1.54 litres returned in 30 seconds.

    I also wound my compressor down to 25lbs and after taking the cap off I blew through the return lines. Instantly I heard fuel bubbling so no return restriction either.

    Not much to check now, only flow from the distribution heads and I'm not really setup to do that. I'll have to try and source these graduated plastic beakers that Steve talks about.
     
  24. uzz32soarer

    uzz32soarer F1 Rookie

    Sep 9, 2006
    3,088
    Melbourne, Australia
    Full Name:
    Robert Hayden
    Something else just came to mind here.

    I'm only testing the lambda, not CO's, hydrocarbons etc. I just spoke to the guy refurbishing the heads and he's worried that cam timing may be out. He has seen many issues with Porsche boxer style engines that have shown up when the cars were put onto a five way gas analyser. Cam timing was out and even though the Bosch units were performing faultlessly, at constant light throttle, the cars started bucking and surging and generally throwing themselves around.

    FF here in Melbourne also mentioned this to me as a possibilty on Sunday.

    What's your thoughts on this, and is it possible to check the cam timing with the engine still in the car.
     
  25. carguy

    carguy F1 Rookie

    Oct 30, 2002
    3,402
    Alabama (was Mich.)
    Full Name:
    Jeff
    The "approximate" way to check cam timing is to get the motor at top-dead-center and look and the "reference" pointers on the rear cam belt covers in relation to the marks on the cams. This method will tell you if something is really screwed up.

    Space is very tight for doing an actual cam timing check with a degree wheel, but it "may" be possible. At the front of the motor you will either have to remove the crankshaft pulley, or figure some way to mount the wheel onto the pulley, while keeping in mind that you will need to turn the crankshaft over with a 36mm socket on the harmonic balancer bolt. Then you will have to pull off the cam cover and try and mount up a dial indicator to the camshaft lobes at #1 cylinder (you will want to degree both intake and exhaust cams).

    As for the cam timing causing the lean condition and the surging, would this mean that the intake cams are slightly advanced from the optimum timing, and not allowing enough time (intake valve open) for sufficient fuel to enter into the combustion chamber? I would like to learn more about this....can anyone explain it?
     

Share This Page