Check engine light

[Adam in CO]

Is running a couple of lean codes. New fuel pump and O2 sensors have not solved the problem. Any ideas? Intake manifold, maybe?

[NewHummerGuy]

Originally Posted by Adam in CO

Is running a couple of lean codes. New fuel pump and O2 sensors have not solved the problem. Any ideas? Intake manifold, maybe?

Mine came on a couple months back. Took it in and was the catalytic converter. 35k miles on 2003. They just replaced as they are covered for like 80k miles or something.

Just a thought.

[f5fstop]

Could be a cat, or:
Bad injector (run a can of Techron through the fuel system. might help, it does a great job of cleaning injectors)
Bad vacuum hose (you can try the old propane trick to see if idle increases when the propane comes near a cracked vacuum line)
Opening past the MAF sensor in the tube to the throttle body

[PARAGON]

Originally Posted by f5fstop

Opening past the MAF sensor in the tube to the throttle body

this is likely if you had anything done to the front of the engine, ie A/C, belt, etc. They will take off the deer antlers of an intake system (in my case it was just a straight aftermarket MIT) and when they put it back on they don't take their time and pinch the rubber seals.

[timgco]

Originally Posted by PARAGON

this is likely if you had anything done to the front of the engine, ie A/C, belt, etc. They will take off the deer antlers of an intake system (in my case it was just a straight aftermarket MIT) and when they put it back on they don't take their time and pinch the rubber seals.

The biggest issue here will be to diagnose anything in Adam's engine bay.

I have seen this before and I bet it has 100lbs of mud caked everywhere. There may be rodents living in there by now.