86 assistance please! (idle problem) (with movie and a couple pics)
#1
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I have just installed an 86 engine and complete wiring harness into my 81 euro, and I am needing some guidance,
the car doesnt idle right,
it seams like it drops off and then catches, and just repeats this, on each pulse there is a puff of black smoke,
sometimes the idle will smooth out and idle normally and there is a steady stream of black, indicating that it is running to rich, so I doubt it is a vacuum leak,
I am am wondering if it is possible that a couple of the wires in the 14 pin (by the passenger side camshaft) could be in wrong as the connector was badly damaged? or if there is a sensor that would be causing this,
it this state, I cannot rev the engine up at all, and while running I am pulling exactly 10 in HG of vacuum, which I know should be 18-20
while the car is pulsing the vacuum pulses from 5-15in HG,
also I am wondering if the fuel dampners, fuel regulator, and the EZF vacuum are a throttle vacuum, or manifold vacuum preassure, becuase I am not getting any vacuum to these devices under idle or pulse, and I have it off the valve on the throttle body that the factory manual states to have it off of,
at this time I am looking for opinions as to what to try next or what to look for,
TIA Colin J
the car doesnt idle right,
it seams like it drops off and then catches, and just repeats this, on each pulse there is a puff of black smoke,
sometimes the idle will smooth out and idle normally and there is a steady stream of black, indicating that it is running to rich, so I doubt it is a vacuum leak,
I am am wondering if it is possible that a couple of the wires in the 14 pin (by the passenger side camshaft) could be in wrong as the connector was badly damaged? or if there is a sensor that would be causing this,
it this state, I cannot rev the engine up at all, and while running I am pulling exactly 10 in HG of vacuum, which I know should be 18-20
while the car is pulsing the vacuum pulses from 5-15in HG,
also I am wondering if the fuel dampners, fuel regulator, and the EZF vacuum are a throttle vacuum, or manifold vacuum preassure, becuase I am not getting any vacuum to these devices under idle or pulse, and I have it off the valve on the throttle body that the factory manual states to have it off of,
at this time I am looking for opinions as to what to try next or what to look for,
TIA Colin J
Last edited by Lizard928; 04-22-2005 at 12:09 AM.
#4
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Ok, I checked the vacuum off the throttlebody for the dampners and fuel pressure regulator, and map, it had come off, so I reconnected it.
the car is still running really rich and not idling correctly, and is tough to start,
since I fixed that leak the vacuum went up to a stable 15 HG, and there is no leaks from there, the only other thing connected is the brake booster,
to give alittle info I have deleted the air pump, and the crankcase no longer vents to the intake, all those empty spots were capped off.
I also thought that a vacuum leak would cause a lean condition and not a overly rich situation. and with 15 in HG of vacuum now I should be able to rev the car up and I am unable to,
and I tested the circuit to the EZK and dampners and regulators and it showed no leaks now.
unfortunatly with the sucking noise coming out of the air box there is no way to hear any vacuum leaks.
any further suggestions?
the car is still running really rich and not idling correctly, and is tough to start,
since I fixed that leak the vacuum went up to a stable 15 HG, and there is no leaks from there, the only other thing connected is the brake booster,
to give alittle info I have deleted the air pump, and the crankcase no longer vents to the intake, all those empty spots were capped off.
I also thought that a vacuum leak would cause a lean condition and not a overly rich situation. and with 15 in HG of vacuum now I should be able to rev the car up and I am unable to,
and I tested the circuit to the EZK and dampners and regulators and it showed no leaks now.
unfortunatly with the sucking noise coming out of the air box there is no way to hear any vacuum leaks.
any further suggestions?
#5
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Sounds like it its running like my 86 when I got it... I ended up replaceing the MAF and O2 sensor.... Not sure what on your car is new or from the donor and what is from the original euro... if you put the harness LH unit from the donor and have the vacuum and fuel system from the donor 86 as well then you should be able to get it to run right... it you never saw the new engine running I would suspect MAF.... maybe idle stabilizer... On the vacuum ... if everything is from the donor then it shoud be good right??? but vacuum is kind of voodoo for me... hook them up it right... have a leak your fu&@ed
send any pics and feel free to reply with specific questions regarding my 86...
LO
send any pics and feel free to reply with specific questions regarding my 86...
LO
#6
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I would think it should be pulling 18 at idle, but if its running rough that could cause it to drop. I just had a rich running problem with my 951 and after exhaustive research i found it was the TPS. 10 mpg in a 4 cyl turbo. If you are sure all the vacuum lines are correct and no leaks, I would suspect a sensor. Speaking of O2 sensors, are you sure yours is hooked up correctly.
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#8
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Definitely check the OXS for output. Also swap in a different MAF. But I suppose John Speake or Rich Andrade could help if there is a brain wiring faux pas.....
#9
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hey Heinrich, I fired you off an e-mail not needing the injector any more,
I have at this time a BRAND new O2 sensor (well it has been sitting in a box for over 1 year but never used.
the engine came out of my 86 and was running PERFECTLY, however that was about 9 months ago give or take a couple,
I have tried disconnecting the TPS and it didnt seem to make a difference,
I have a fuel pressure tester that i hooked up, but I was out of fuel, I will add more fuel tomorrow and see what my rail pressure is.
thanx for the assistance on this, oh sharkmeister if you read this, do you happen to have your old MAF?
I have at this time a BRAND new O2 sensor (well it has been sitting in a box for over 1 year but never used.
the engine came out of my 86 and was running PERFECTLY, however that was about 9 months ago give or take a couple,
I have tried disconnecting the TPS and it didnt seem to make a difference,
I have a fuel pressure tester that i hooked up, but I was out of fuel, I will add more fuel tomorrow and see what my rail pressure is.
thanx for the assistance on this, oh sharkmeister if you read this, do you happen to have your old MAF?
#10
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ok well I have been doing some reading,
I am going to unplug the maf and make sure it is getting voltage and also try limp home mode,
I am going to try and get Glenn to come over and try my brains in his car to make sure that they are not faulty,
however does anyone know how to get ahold of the guys at http://www.jdsporsche.com/index.html
I e-mailed there info@jdsporsche.com and it was returned,
or does anyone know how much they charge and what the turn around time is on the MAF and LH 2.2brains, or do the 2.2 versions have the same prob as the S4?
I am going to unplug the maf and make sure it is getting voltage and also try limp home mode,
I am going to try and get Glenn to come over and try my brains in his car to make sure that they are not faulty,
however does anyone know how to get ahold of the guys at http://www.jdsporsche.com/index.html
I e-mailed there info@jdsporsche.com and it was returned,
or does anyone know how much they charge and what the turn around time is on the MAF and LH 2.2brains, or do the 2.2 versions have the same prob as the S4?
#11
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Probably not your brains, Colin. Our version is a lot sturdier than the S4 stuff. It almost sounds like it is firing out of sequence. recheck your wires and rotors.
#12
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hey rotors never came off, and I have double and triple checked my wires sequence, I ran the car at night and saw no light dances on factory wires but I will be replacing them soon,
and I popped the cover off my LH box, and realized that it was alot better than the S4 units, lol
I am going to check the pressure tomorrow and unplug the maf *crosses fingers that it is fine*
and I popped the cover off my LH box, and realized that it was alot better than the S4 units, lol
I am going to check the pressure tomorrow and unplug the maf *crosses fingers that it is fine*
#13
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Hi Lizard you may want to check the following: fuel clean and fresh?? these cars hate bad fuel especially 85-86cars.. try a can of berryman fuel injector cleaner. if not avail next best thing is techron.. since you said it runs fine some times you can check your idle stabilizer, I can get the measurements for you if needed ( i belive on Johns site ) on what your maf should be reading if working ok. Lastly you can check how far open your air bleed screw is set for. A slight adjustment may help compensate for a not so accurate MAF reading.
Dave...
Dave...
#14
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Hey Dave, I put the tank out of the 86 in there, and it was BONE dry when I installed it, and I flushed the lines out and nothing came out of them, all brand new fuel, I will be checking the MAF either today or tomorrow,
and checking fuel pressure.
and checking fuel pressure.