Check for updates for your on board computer, if needed have it flashed. I had to do that, on a Jeep Grand Cherokee limited. Fixed the problem.
If you are loosing power, you might check to see if your catalytic converter is clogged up, I had that problem on another Jeep, just removed the catalytic converter and it ran like a new one again. This is not recommended because it is not legal. Don't have the vehicle any more, it is being used as a ranch vehicle only now. Still runs great.
Hope this helps,
Mark
If you are loosing power, you might check to see if your catalytic converter is clogged up, I had that problem on another Jeep, just removed the catalytic converter and it ran like a new one again. This is not recommended because it is not legal. Don't have the vehicle any more, it is being used as a ranch vehicle only now. Still runs great.
Hope this helps,
Mark
How long since you have done a full tune-up? Electronic Ignition Module and and spark plugs and all wires associated? besides that, its very possible you have a phantom GM electrical Gremlin, which would have to be significant ie: A/C, Heater Core, Instrument Panel. Best bet is to do the full tune-up, then wipe your computer, have it factory reset, by either the dealership or a mom and pop shop if they have the capability. I remember my pop's 03' having generally the same issue, and he did full ignition tune-up, wiring harness, and any major system in the rig got an overhaul and new wiring or components.
Yeah, the "light" is not the problem. It actually goes into reduced engine power and acts like it is running on 3 cylinders.
I haven't run a Chevy in a few years, but that sounds like a computer problem, a different on board computer may be needed. If you weren't getting the codes you have, I would say you have a fuel pump problem, but with the codes and power fail, I would say computer.
Isn't their a separate chip that actually controls that ability, the eco-mode or whatever, have you had anyone check that specifically, might be that it is malfunctioning, and something is telling it the wrong speed, or RPM's. Like if your going 40 and accelerating to freeway speeds, does it happen then? Does it go away after a certain speed?
We had similar issues with our Lincoln LS and we would replace some kind of fuel injector thing and it would be fine then the next day or the next week it would happen again. Eventually we just had to tell them to replace the remaining ones because they were all failing within days or weeks of each other. Once all the injector thingies (that's as technical as I can remember lol) were replaced the car ran perfectly but, man, what a PIA it was for the car to keep going into "limp home" mode.
Good luck on your truck...I'm no mechanic obviously.
Good luck on your truck...I'm no mechanic obviously.
That's not a computer problem, that's the computer doing what it's supposed to do--going into a fail-safe mode to protect the car and its occupants. In a drive-by-wire system (which most, if not all cars built in the last several years use), you don't have direct control of the throttle, you're just telling the computer where you want it to be set. In a case like this, the computer no longer knows for sure where the throttle is set, so it no longer has full control of the engine, and it reduces power to prevent a potential run-away condition. (If you ever see up-close spy shots of test mule vehicles, you'll often see a big red button on the dash--it's there to kill power to the computer, because the computer doesn't have the fail-safe code yet.)
Just an educated guess, but I suspect that they were replacing the COPs (Coil On Plug). On 2nd Gen LSes ('03-'06), when certain COPs fail (usually on cylinder 4, due to its proximity to the PCM), they can produce RF interference that the PCM sees as a failing ETC (Electronic Throttle Control). When that happens, the PCM goes into fail-safe, or "limp home" mode. A tech experienced in working on the LS will usually start with the COPs when presented with an apparent ETC failure.
The COP-induced failure may actually be a possibility here, too, but I don't know enough about GM engine control systems to know if it's likely.
