Question About ECM Replacement

[1990 Lumina Euro Coupe]

I'm having to replace the ECM in the 1989 Cutty.

 

I ordered the unit, and it has arrived. The question that I had is that the instructions say that you should check all of the circuts for shorts because ECM's usually do not fail without a circut problem.

 

Do I really need to check taking the age of the car into account? I always believed that when they failed it was usually because of age, and that you just replaced them.

 

Has anyone here ever installed one and not checked?

[Guest Anonymous]

Has anyone here ever installed one and not checked?

 

Yes.

[93CutlassSupreme]

that'd really suck to check every circuit for a short

[1990 Lumina Euro Coupe]

 

Has anyone here ever installed one and not checked?

 

 

Yes.

 

Thanks, Turby. That puts my mind at ease.

 

that'd really suck to check every circuit for a short

 

Yes it would. I think that they are putting it in there as a CYA("Cover Your Arse ") statement. Taking into account that the instructions are about as long as my arm, elbow to fingers, and are filled with about three times more "DON"T" that 'DO" statements, I think they are just watching out for themselves.

[wolfy950]

I replaced mine a week ago without checking everything. I did replace the alternator about a week before that and also one sensor. I was still getting strange error codes and the car would just about not even run so I did the ECM. Fixed everything.

[GnatGoSplat]

ECM's usually do not fail without a circut problem

 

Ah, but an ECM from an 89 Cutlass (and I'm pretty sure all W-bodies 88-93) often fails without a circuit problem.

 

They fail because of solder problems. Someone who worked for a company that remanufactures ECMs once posted somewhere (GM-ECM list or newsgroups) that this breed of ECM almost always is repaired simply by washing/stripping the chemicals off, and reflowing the solder on the board.

 

I wouldn't worry about checking for shorts. In the rare occurrence that there is a short that kills the ECM, it is usually in one of the injectors.

[1990 Lumina Euro Coupe]

ECM's usually do not fail without a circut problem

 

Ah, but an ECM from an 89 Cutlass (and I'm pretty sure all W-bodies 88-93) often fails without a circuit problem.

 

They fail because of solder problems. Someone who worked for a company that remanufactures ECMs once posted somewhere (GM-ECM list or newsgroups) that this breed of ECM almost always is repaired simply by washing/stripping the chemicals off, and reflowing the solder on the board.

 

I wouldn't worry about checking for shorts. In the rare occurrence that there is a short that kills the ECM, it is usually in one of the injectors.

 

Taking int account that GM cars of the 1980's to mid-90's have a reputation for bad solder, I don't doubt that in the least.

 

The "Low Fuel" light(mine shows a gas pump) in my 1991 Grand Prix stays on all of the time because of bad soldering.(I'm going to have to repair the shift indicator, and will reflow the solder then.)

 

I have an 86 Trans Am that the display on the radio was frozen on 9:26. The "set" light was always on. I took it to have it repaired and guess what? Bad Solder. The fellow that repaired it for me even made a statement about GM cars of this era and the poor soldering jobs.

 

Thank you for again putting my mind at ease. I'm going to install it tommorow. I feel alot more secure now.