# [SOLVED] 89 cavalier ecm problem



## auzzie2 (Feb 2, 2012)

*1989 Chevy Cavalier Z24 Convertible 2.8L runs and drives. Dies on take off sometimes. No codes or any data from the ecm. unable the scan ecm. No code 12. I have nothing. Starts good sometimes and then have to hold gas to the floor somethmes. I'm waiting to get the car back from the top place. *


----------



## octaneman (May 13, 2009)

*Re: 89 cavalier ecm problem*

Hi auzzie2


No response from the computer is a very high probability that the communication bus line is cut or its dead.


----------



## auzzie2 (Feb 2, 2012)

*Re: 89 cavalier ecm problem*

I will be getting the car back today if it will run. I will run some tests.


----------



## auzzie2 (Feb 2, 2012)

*Re: 89 cavalier ecm problem*

Got the car back. ran ok for 1 mile then starter stalling 3 more miles and ran very bad. Got a code 12 but no other codes.


----------



## octaneman (May 13, 2009)

*Re: 89 cavalier ecm problem*

Check the ground wire to the computer if its loose or corroded, the ground wire should be bolted on to a 1/2 inch threaded bolt that holds the coil. Use emery cloth to clean the terminal that makes contact with the surface.


----------



## wolfen1086 (Oct 4, 2007)

*Re: 89 cavalier ecm problem*

Also check the body to frame grounds on some Chevy's they used the body to ground the car to the frame in stead of a wiring to the main ground


----------



## auzzie2 (Feb 2, 2012)

*Re: 89 cavalier ecm problem*

Thanks Octaneman & Wolfen1086. I checked & cleaned all the grounds But the one at the coil packs. I will check there next. I tryed grounding the aldl at 1500rpm and no change in rpm & no codes the service engine light just flashed very fast when grounded.


----------



## octaneman (May 13, 2009)

*Re: 89 cavalier ecm problem*

Hook up a fuel pressure tester and test the pump's output pressure, from what you told me so far the engine appears to be starving for fuel.


----------



## auzzie2 (Feb 2, 2012)

*Re: 89 cavalier ecm problem*

Fuel pressure over 40psi. has a new fuel pump, All new injectors, vacuum lines. I still dont see how there is no codes. It should trigger a code when I ground the aldl connector when running. I will try to unplug some of the senors to see if I can trigger some codes. I will get back to you with the results.


----------



## octaneman (May 13, 2009)

*Re: 89 cavalier ecm problem*

You can't trigger codes through the ALDL while the engine is running , you risk frying the computer. The only way you can trigger codes is by disconnecting any engine sensor and snap the throttle for the computer to pick it up. The 89 is OBD1 to get the codes you jump the pins on the ALDL and the radiator fan should come on. The other way is through a scanner.


----------



## auzzie2 (Feb 2, 2012)

*Re: 89 cavalier ecm problem*

Unpluged O2 sensor, EGR, idle air ect... no codes stored and service engine light did not come on. Still did not check ground at coil pack. Will do today.


----------



## wolfen1086 (Oct 4, 2007)

*Re: 89 cavalier ecm problem*

Ok I have to ask did you buy this car used? if you did check teh dash board where the service engine light is located at and see if theres a bulb in there, some people take out the bulb before selling the car to make it look like its in A1 condition which is a federal crime.


----------



## Marine76 (Feb 17, 2012)

*Re: 89 cavalier ecm problem*

I had the same problem with an 88 Olds with 2.8 engine. I checked codes and it showed code 12 which means everything was ok. Replaced computer and solved problem but you will probably have to take the car to a gm dealer to have the computer flashed.


----------



## auzzie2 (Feb 2, 2012)

*Re: 89 cavalier ecm problem*

Thanks for the update. Maring76 
I thing I will go to the junkyard to see if I can find one to try. There is alot of cars that have that ecm, I have a list. I will post my findings soon.
Need to have the car on the road by May.


----------



## auzzie2 (Feb 2, 2012)

*Re: 89 cavalier ecm problem*

Got scaner to use. Problem was bad wire cont. at coolant sensor. Runs good now. Will now go into closed loop. Have not had on road test yet will let you know what happens. Thanks for all the input.


----------



## wolfen1086 (Oct 4, 2007)

*Re: 89 cavalier ecm problem*

Keep us posted


----------



## auzzie2 (Feb 2, 2012)

*Re: 89 cavalier ecm problem*

Replaced coolant temp sensor and pigtail. Runs great. 
Thanks for all your help,


----------



## Basementgeek (Feb 7, 2005)

*Re: 89 cavalier ecm problem*

Thanks for letting us know. I will mark this posted solved.

BG


----------



## Innvader03 (Nov 13, 2012)

I am glad that solved your stalling problem but on my car, it has not been solved. 
I have changed the AIG sensor, the fuel positioner, and the crank shaft position sensor. This helped my car run better, but didn't fix the car. 
When it is started when it is cold, it runs like a dream. As soon as it gets at operating temperature, it will just quit for no reason. If you give it a lot of gas, it will die, if you go around a corner, it will die, if you are just driving, it might die. 
Once it dies, usually you have to let it sit for about 45 minutes because it will not restart. 
I have changed the temperature sensor, that didn't do anything. 
I have changed the the hoses to the IMAP sensor, just made it run smoother after it was changed. 
I had to change the ignition, the last one locked up tight. The steering wheel currently can be moved up and down about 2 inches. 
Someone borrowed my car and used the tilt, messed it all up.
The head gaskets were just changed a month ago along with a battery and a starter. 
Trying to keep it on the road is becoming a real headache. 
It flashes code 12, all clear. 
The fuel pump and filter were replaced. The pump wasn't functioning right and the filter was clogged. They were checked yesterday for pressure, good to go. 38 to 40 psi. 
Plugs were changed 3 months ago. The ignition module was changed a month ago and a coil pack 1 month and a week ago. 
This problem of dying after it gets warm needs to quit. Any suggestions?
I read the last thread and I am starting to think it might be a ECM. 
If anyone replies, I will post if it works or not. Thank you.


----------



## wolfen1086 (Oct 4, 2007)

WOW all that wrong and no codes? if it was the ECM it should pop a cod for that too, unless its like my old 82 Cav and the whole thing is burnt out.
How many miles are on yours? does it smoke any at all when warm? Are there and rattles, pings, clunks when warm?


----------



## Innvader03 (Nov 13, 2012)

I had changed the motor out at 89,113 miles. It had overheated, blew up the motor. Since then, have changed 3 coil packs, the last one about 2 months ago. 
No smoke or any noise when it runs. When it runs, it runs great. After it heats up, it just dies like it isn't getting any fuel. 
When it starts working again, you can hear the fuel rush to the fuel injectors and then it runs great again. 
The fuel pump has been replaced and it was tested to be good yesterday. 
It was supposed to be tested again, but it hasn't yet today. Hopefully by 3 p.m., I should have some results back.


----------



## wolfen1086 (Oct 4, 2007)

How many miles are on the engine you installed? If its not re-manufactured run a compression test. Also check the fuel system pressure, also check all lines valves and connectors for air getting in, a pump isn't always the culprit in a engine not running right, check the power supply going to the coil packs, and the grounds,


----------



## Innvader03 (Nov 13, 2012)

It has a remanufactured engine. I would say its about 25,000 miles into the new engine. 
The fuel pressure was checked at 38-40 psi, pump was changed. 
I was told the ecm was the culprit, so I bought one and changed it for about $110.00. 
However, it didn't do anything but waste my money. It still dies. If it has been running and I shut the motor off, it will not run for about 30 to 45 minutes. Won't start, just crank and crank. 
If I floor it or go around a corner, the engine shuts off. 
I am going to talk to the mechanic in the morning and see what he says. 
My steering wheel also goes up and down about 2 inches, maybe it has something to do with it. 
I just don't know at this point.


----------



## wolfen1086 (Oct 4, 2007)

the steering wheel going up and down 2" will only have anything to do with it if the ign switch wires are being pinched and shorting the run cycle out


----------



## Innvader03 (Nov 13, 2012)

The car shut off again this morning. It seems to be happening more frequently. Used to, it would last at least 15 minutes before the shut downs would occur.
When it started back up, you can hear the fuel rushing towards the engine. It makes me thing the fuel pump lost its power or something. Or, maybe that something reset to give it some power again. 
I am going to check the ground wires next to the coil pack this morning. 
I am also going to have to call Autozone to see if they will take the ECM back since it did not fix the problem.:angry:


----------



## wolfen1086 (Oct 4, 2007)

Sounds like your lose pressure to the fuel system somewhere. or else there's a blockage somewhere


----------



## Innvader03 (Nov 13, 2012)

It has to be the fuel injectors. I returned the ECM this morning. 
I can't handle it anymore if it is not the fuel injectors. 
I stranded me 3 times today. no more
I dropped it off at a mechanics house. they will replace it tomorrow. It better come back working or i might put ether in the car and burn it. 
I am tired of it not working. enough is enough.


----------



## Innvader03 (Nov 13, 2012)

It is legal burn your car, right? I own it, I won't be claiming insurance against it. I just can't stand it constantly breaking anymore. Burn it, and turn in to recycling if the fuel injectors don't work.


----------



## Basementgeek (Feb 7, 2005)

The car will be worth more as salvage/scrap if you don't burn it. If you are in the USA, the law will probably get you for open burning.

You can try your local "junk yard" for the injectors.

BG


----------



## Innvader03 (Nov 13, 2012)

The problem is finally SOLVED!!!!!!!:dance:
I had both fuel rails replaced. (fuel injectors) . Once the injectors were replaced, it runs like a scalded dog. It will spin the tires upon take off, not that I want to. No more missing, stalling, or dying. No more not starting for an hour. 
All the problems with that have vanished. 
The old fuel injectors were dirty, black stuff on them and the rubber seals, some of them was split. Only two fuel injectors looked any good, the rest, BAD. 
I am so happy its fixed.  
I still have to fix the steering wheel, it moves two inches, and it seems my motor mounts are going back, but those ain't going to strand me in a parking lot. 
Thanks for everyone's help. :smile:
Great suggestion , Basement Geek.... $30 bucks.


----------



## Basementgeek (Feb 7, 2005)

You are welcome, glad everything went well.

BG


----------

