2001 gmc 8.1 ECM upgrade question

[Monte Howard]

I have a 2001 GMC 2500 HD, the ECM isn’t sending a pulse signal to the #4 injector. So I need to purchase a new ECM I am assuming. Anyone have experience upgrading the ECM on these 8.1 chevys for more performance for towing?

[vette5148]

You should check for continuity between the injector plug in and the corresponding pins on the ecm plug in to make sure there isn't a break in the wiring somewhere. Hate to put in a new computer and it does the same thing. Have seen a broken wire or a mouse damaged one before.

[Alan Roehrich]

Originally Posted by Monte Howard

I have a 2001 GMC 2500 HD, the ECM isn’t sending a pulse signal to the #4 injector. So I need to purchase a new ECM I am assuming. Anyone have experience upgrading the ECM on these 8.1 chevys for more performance for towing?

A little late to the game here. It's pretty rare to drop a single injector driver in the ECM. Usually there's an attending wiring or injector problem, or both.


The factory tune is woefully bad, there's no ignition timing, and the fuel mixture response is intentionally delayed. There's a significant amount of power and fuel economy there. Especially combined with a good exhaust system. That does not mean it has to be loud.



The 8.1 responds to tuning, and free flowing exhaust, the performance restriction, however, is the intake manifold itself, and the camshaft, there are people who modify the intake, and Comp has a good cam for it, and it can be converted to adjustable valvetrain. I'd suggest you search the Duramax forums, and the Silverado forums.