please help
please help my buddys 95 formula has been acting up lately and we just cant figure it out. It has a new opti and icm. when it first threw a code it said the icm was grounding out. so we checked the wiring and could not find anything wrong. the car would still run but it was idleing rough. now it wont start at all, when you turn the key forward the fans turn on right a way,the fuel pump starts but stays on way to long, all the injectors sart to pulsate, and all the relays start clicking. so we hooked the scanner back in and when we did the door locks locked then unlocked, and it said that there was no comunications going on like if it was not even pluged in. if we keep cranking it over and over it will barely turn on for like 20 seconds but it smells way to rich. the fuel pressure is fine. We are leaning towards the ecm. any help would be really appreciated. thanks in advance.
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Did you try the old ECM? I had the locks on a buick do that when I was hooking the ground to the engine.
The ECM controls the injectors so if they are pulsed the ECM 'thinks' the engine is running. Loose grounds could fool the ecm.
Verify ALL grounds the harness has many grounds meet atthe front of drivers side head. Fix them make new conections to the wires.
Hope this gets you some different data.
The ECM controls the injectors so if they are pulsed the ECM 'thinks' the engine is running. Loose grounds could fool the ecm.
Verify ALL grounds the harness has many grounds meet atthe front of drivers side head. Fix them make new conections to the wires.
Hope this gets you some different data.
we have not replaced the ecm only the icm was replaced. and we tried the old one but still no dice. we have looked over the whole harness we even took off all the grounds and cleaned the points of contact.
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From: I moved to over there
The engine will smell rich if it cranks along time without starting
I still think it is a ground to the ECM. The scanner caused things to changeI I think the system got a missing ground somehow through the scanner. Get a noid light check that the injectors are clicking from the first time it turns over.
If the injectors are 'firing' it has to be on ignition side. ICM you replaced but leaves a lot to be wrong and if it is not grounded or powered., rotor or cap bad weak coil etc..
Also noids flashing from start means ecm has ground and is trying to start motor...get it to either gas or spark
Hope this helped
I still think it is a ground to the ECM. The scanner caused things to changeI I think the system got a missing ground somehow through the scanner. Get a noid light check that the injectors are clicking from the first time it turns over.
If the injectors are 'firing' it has to be on ignition side. ICM you replaced but leaves a lot to be wrong and if it is not grounded or powered., rotor or cap bad weak coil etc..
Also noids flashing from start means ecm has ground and is trying to start motor...get it to either gas or spark
Hope this helped
yea thanks. i know i am getting fuel. i changed injectors. checked the fuel regulator and the fuel pressure. I only get spark sometimes and when i do it is weak. what would cause everything to act up like that even my fans. i am pretty sure i checked all the grounds,but maybe i missed one. is there somewhere i can go that will show me all the grounds going to the ecm. How often do the ecm's themselves go bad?
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if you didn't use a noid it could be ocassional fuel. That makes a difference, if injectors fire consistently that means the ECM is ok that is why i asked.
Good but...
how do you know it is occassional and weak?
Many things that is why you hae to be methodical or you will never find the problems. Often there are more than one and a shotgun approach finds maybe one.
I will attach pics in a sec
Seldom and I do not think yours is bad.
how do you know it is occassional and weak?
Many things that is why you hae to be methodical or you will never find the problems. Often there are more than one and a shotgun approach finds maybe one.
Seldom and I do not think yours is bad.
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if you didn't use a noid it could be ocassional fuel. That makes a difference, if injectors fire consistently that means the ECM is ok that is why i asked.
well im not to sure on that all i know is that they do fire. how do i check if they are firing consistantly?
how do you know it is occassional and weak?
i used a spark tester that you put between the plug and wire and the light does not turn on and very rarely when it does it is just enough to make the light glow.
Many things that is why you hae to be methodical or you will never find the problems. Often there are more than one and a shotgun approach finds maybe one.
that is exactly what i am trying to do. i want to make sure i find the problem with out having to spend unneccisary money. i am just fustrateed because it has been sitting for like 3 months.
I will attach pics in a sec
pics would help a lot. thanks for your help.
Seldom and I do not think yours is bad.
ok i just dont know what else it could be. i am going to check over everything tomorow. i am also going to check if i am getting the correct voltage to everthing.
well im not to sure on that all i know is that they do fire. how do i check if they are firing consistantly?
how do you know it is occassional and weak?
i used a spark tester that you put between the plug and wire and the light does not turn on and very rarely when it does it is just enough to make the light glow.
Many things that is why you hae to be methodical or you will never find the problems. Often there are more than one and a shotgun approach finds maybe one.
that is exactly what i am trying to do. i want to make sure i find the problem with out having to spend unneccisary money. i am just fustrateed because it has been sitting for like 3 months.
I will attach pics in a sec
pics would help a lot. thanks for your help.
Seldom and I do not think yours is bad.
ok i just dont know what else it could be. i am going to check over everything tomorow. i am also going to check if i am getting the correct voltage to everthing.
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That is the way to do it. Don't assume. Easy to do but if you verify everything you will be fine. It is painful but if you are methodical you are less likely to over look a problem.
NO one finds it easy it is time consuming. BUT once you eliminate things it will come down to a couple possibles that we should be able to eliminate and hopefully find the cause.
NO one finds it easy it is time consuming. BUT once you eliminate things it will come down to a couple possibles that we should be able to eliminate and hopefully find the cause.