ughmas

Ok so my 88 gta is still broken.. heres a summation of whats happened

Car was running fine for a month or 2 but had a hard start sometimes

on easter the car died while stopping at a red light, started back up a couple times and continuously died while turning over the tailpipes were letting out alot of smoke with a heavy gas smell. so i drove a little bit more and it cut out one final time so i left it and walked home I got car to my house after a couple tries the next day (it was still running really bad).

checked codes... nothing but 12
Changed fuel filter
tested fuel pressure
changed fuel pressure regulator spring/gasket (was leaking)
ICM passed all tests 3 times at 2 different auto parts stores
pickup coil ohm tested good
ohmed all the injectors they were all 17

think the car is flooding itself the injectors are acting all screwy with a noid light sometimes it will just be solid when the key is on and stay solid sometimes it wont come on at all, sometimes they will pulse correctly.

with key in on position all the injectors make a cracking noise sometimes and you can feel them vibrating almost as if they are all being shorted out, when the crackling sound happens the noid lights change with the crackle

all the wiring looks good with the exception of a black connector above the transmission dipstick that looks a little melted not sure what its for have a pic of it if that would help

can get it to start only when pumping it alot and it idles terribly/stalls out


im just not sure what to do

also im not sure if its related at all, but its very worrying, i was taking off the air hose and there was a bunch of oil in it and the intake manifold, which wasnt there before at any point, but its weird because the car hasnt really run for more than a few seconds from when there wasnt oil to where there was a bunch in there. i looked at the PCV it was fine

anyone have any advice as to were to start next im getting very frustrated

ughmas

bump been without my car for too long

ughmas

ughmas

SpitotRs305

what was the fuel pressure reading?
explain this crackling a bit more... do all the injectors do it? one?

i would start by removing the fuelrail and injectors as a unit and prime the system see which ones are open when they shouldnt be then work from there....

and change your oil before running the car again

ughmas

the fuel pressure was ~40 psi, the crackling is kind of random, sometimes the top right 2, sometimes all of them. i changed the oil very recently before the car died.

what do you mean prime the system?

RFmaster

ughmas

1) Can you post a picture of that connector?

2) ECM controls injectors by pulling one side of injector coil to ground. This is the dark green and dark blue wires. Injectors are arranged in batch groups and 4 of them are fired at the same time. The other side of injector coil is connected to +12 Volt (pink or red wire). For the ECM to fire injectors it must receive a DRP signal from distributor. I would suggest checking EST module inside dizzy - possibly replacing it. Another reason we see here for lack of injector fire is dizzy with missing magnets.
Otherwise, unusual wiring harness suspects should be checked.

//RF

ughmas

1) here is that connector, someone already posted a response

https://www.thirdgen.org/forums/tech...d-causing.html

2) Where is the est module located? its not the same thing as the ICM is it? Ive had the ICM tested several times, the magnets look good in the dist, all the wiring minus the connector above looks good.

could it be the ECM itself?

RFmaster

ICM = Ignition Control Module inside dizzy. If it tests out OK the only other possibilities left are bad ground reference wire between ECM and dizzy and ECM itself. Do you have MAF on your car???

//RF

bgood71

If the coolant sensor shorts out ,it'll cause the car to run so rich that it will stall and not restart. Just a thought, worth looking at.

ughmas

OK i will take a look at that tommorow morning

yeah the ICM tested good i tested it 4 times, yeah there is a MAF, i dont beleive it could have any effect on the injectors until the car is running tho

ughmas

just looked at the coolant sensor, doesnt look like anythings wrong with it, and its been working good

RFmaster

ughmas

Lets take it step by step. I would chase this problem like this:

1) Basic ECM check. When you turn ignition key from to run position do you get SES light to on- off - on - you can hear fuel pump priming for about 2 seconds?

2) Get DVM - measure injector voltage (ign =on, engine not running) - injector should have two wires: Light Blue and Red - Cyl 1, 3, 5, and 7 and Light Green and Red Cyl 2, 4, 6, and 8. Red wire should be connected to ignition-on fused. Light blue wire is to Pin D15 and Light Green is to Pin D16 of the ECM interface connector. Get a Noid test light - one connector goes to ground and the other back probing the light blue, light green side of injector connector wire. With engine stopped and ignition in run position noid light should be on. During cranking noid should be blinking off periodically.

3) If noid does not blink-off then back probe D15 and D16 at ECM while cranking. If the NOID does not blink off (solid light) ECM is not pulling injector lines to ground - ECM control circuit is bad or ECM is not receiving DRP pulses from dizzy. If NOID is off then there is a brake - intermittent in harness between injectors and ECM connector. Disconnect battery, disconnect ECM from harness an measure D15 and D16 resistance to ground. It should be around 4 Ohms.

//RF