# [SOLVED] 89 Cavalier 2.8L fuel probleom



## BurnoutNova (Sep 14, 2010)

I am having probleoms with an 89 Cavalier. When it's cold, it starts and runs fine. As it warms up it starts to miss and the engine dies with alot of load. It acts like a fuel pump with insufficient volume. I put a pump in, it has good pressure 40-45psi. Good spark, and it has injector pulse. The injector pulse is a little odd. Sort of spiratic and the brightness of the noid light changes as I crank the engine. Once it dies, it will not run. If you crank it wants to run but will not. It WILL run with starter fluid. It seems as no fuel is getting to the cylinders. The injectors I can get to with the upper intake on have 13.2 Ohms of resistance with the engine warm. 

What am I missing?


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## octaneman (May 13, 2009)

*Re: 89 Cavalier 2.8L fuel probleom*

Hi BurnoutNova 

Back in the 80's Chevy cavalier 2.8's had a serious issue with the harness connector to the computer. This caused wide spread problems and no-start conditions that were extremely difficult to trace. The real problem was that the harness connectors would actually disconnect ten thousands of a millimeter away from the computer pins. Special bulletins were handed out to service centers to be aware of the problem, even sealant was also developed to combat that problem which was available only through the dealers. Before the issue was discovered mechanics were replacing the computers by the millions. The fact that you are describing a familiar scenario, my suggestion to you is check your computer connections thats your number one priority. The computer is located on the passenger side behind the glove compartment. 

We'll take this 1 step at a time so nothing is overlooked, be extra vigilant with the connections especially the grounds to the computer make sure they are super clean and tight. The grounds are bolted on the intake manifold near the coil so don't be fooled. 


post back your findings.


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## BurnoutNova (Sep 14, 2010)

*Re: 89 Cavalier 2.8L fuel probleom*

I will double check the connectors at the pcm. I did check the pcm grounds, but they were on the trans bellhousing not by the intake? This one has the coil and ignition module down in the front of the motor not up by the intake.


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## octaneman (May 13, 2009)

*Re: 89 Cavalier 2.8L fuel probleom*

There is that possibility that the grounds are on the bell housing,usually 80's GM cars had the grounds not far away from the ignition coil. In either case make sure they are super clean by using emery paper.


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## BurnoutNova (Sep 14, 2010)

*Re: 89 Cavalier 2.8L fuel probleom*

Octaneman: I checked all the wiring on the pcm... I have a good connection there. Checked my grounds, and the B+ circuits. Also checked resistance in the circuit to my fuel injectors. All is good. 

I started thinking, if my probleom is when its hot then I need to check all of this when its hot and wont run. I warmed it up this morning and pulled my upper intake. Heres the resistance values for my injectors

Cyl 1 = 13 ohms
Cyl 2 = 12.1 ohms
Cyl 3 = 1.5 ohms
Cyl 4 = 4.2 ohms
Cyl 5 = 13.1 ohms
Cyl 6 = 13.0 ohms

This is all when its hot. I know the 2 center injectors are bad of course, but I think the way I understand the fuel injectors are wired, does one bad injector cause the others on the same rail to fail also? I think Im on the right track just dont quite understand if this is all of my probleom


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## octaneman (May 13, 2009)

*Re: 89 Cavalier 2.8L fuel probleom*

Burnoutnova 


Cylinders 3 and 4 are gone and cylinder number 2 is borderline, the fuel injectors are wired parallel which means all have their own circuits. When 1 injector fails it doesn't necessarily mean that all will fail at the same time. It's usually a warning sign that the other injectors have done the mileage and its _a possibility_ not a certainty. Injectors have the capacity that can last the life of the car if they are maintained with injector cleaner. 

So far the readings indicate a serious injector problem and must be repaired accordingly. After installing the new injectors, run the engine with sea foam to break any carbon deposits to maximize engine performance. Just make sure you follow directions to the letter when using sea foam.


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## BurnoutNova (Sep 14, 2010)

*Re: 89 Cavalier 2.8L fuel probleom*

I put 2 new injectors in... Car runs perfect now. I will put some 44K in the tank. 

I am still amazed that it wouldnt let the car run at all with 1 bad injector on each bank. Once the 2 bad injectors cooled down they measured 12.4 ohms. Im glad I checked them hot. 

Thanks for the advice


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## octaneman (May 13, 2009)

*Re: 89 Cavalier 2.8L fuel probleom*

Good Job ! :4-clap:


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## Innvader03 (Nov 13, 2012)

This condition that was posted sounds like my car to a T. I will see if the mechanics can do the ohm testing thing. I have new fuel injection rails ready. I am glad that it fixed your car. I hope that it will fix mine.


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## Basementgeek (Feb 7, 2005)

Innvader03

Please stay with your other thread on your car problem.

This post is closed.

BG


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