Tom Erbil

2003 Tahoe LT... I tried many of the "fixes" that didn't work until I came upon an article from a company who had 1000 of these trucks and he said the number one issue 99% of the time was a

• Defective accelerator pedal position (APP) sensor

I changed this out and after 3 years of off and on reduced engine power, the problem is finally solved.

This was the one item that I didn't change until now.

Hope this helps someone. U can change the sensor without replacing the entire pedal. U will have to unbolt the pedal to remove and replace the sensor but not a bad job. Took about an hour.

Gravydog316

cool
thanks

Fey

Did your reduced engine power also come with error messages of "stabilitrak service" and "traction control offline"?

Tom Erbil

there are two bolts that hold down the pedal assembly to the floorboard. Undue these only and the entire assembly will come loose so you can move it out slightly so you can get to the hex bolts holding the sensor in place. It takes some maneuvering.

Tom Erbil

None of these, just the engine light and "reduced engine power" 2000 RPM Max until i shut it off and let it sit for 3 minutes or so and restart and all would be good for another few hours. It really got bad this year. it was happening quite often. I had to find a fix as my wife drives one of the tahoes. both 2003 tahoe were doing it and both are cured.

Fey

Okay, thank you for the reply. I've got something else going on.

Tom Erbil

Also please note the following as someone was upset that I made it so simple. The issue with most of the vehicle this guy owned was the foot pedal sensor and may not apply to you... Here is my data...

I have two 2003 Tahoes. One is an LT and the other is a Z71. Both with adjustable foot pedal. They require the very same sensor. The codes I received were p1516 and p2135.

mmb617

If you figure out what's causing that post it up as I'm having the same problem.

Not all the time, but occasionally when I try to accelerate from a slow roll the message traction control active comes up and the vehicle ('03 Yukon) has reduced power for 10 seconds or so, then the massage goes away and power comes back. It seems to be happening more frequently as time goes by.

Fey

Here's what we have had done so far with our 2007 Chevy Avalanche experiencing the following error messages: Service Stabilitrack, Service Traction Control, Stabilitrack off, Traction Control off. Reduced Engine Power. Can't drive over 25 mph, had to use towing gear to get it home.

First started in May 2017 at 112k miles. I had the fuel tank switch replaced. It ran fine for several months until August 2017 at 121k miles. This time I was 100 miles from home so had to take it to the closet Chevy dealership. After three days they said it was the ECM.

Here's the mechanics notes on the invoice:
Scanned vehicle and found that fuel pressure sensor was not reading voltage. Dropped fuel tank and found that circuit was short to ground. OHMED out wires on fuel pressure sensor circuit and found that low reference was not an open loop as it should be. Disconnected connector at ECM and circuit changed to having an open loop. Circuit was shorting to ground inside ECM. Replaced bad ECM, First ECM fixed issue but would cause vehicle to lose PWM signal on the injectors causing vehicle to stall. Replaced with another ECM and reprogrammed theft, learned crankshaft sensor and cleaned throttle body plate. Test drove vehicle and problems did not return.

$1080.00 charge. I was told that this was NOT a known issue and since truck was at 121k for this second repair I had to pay for it.

A week ago I got the exact same error messages approximately 4 months AFTER the second repair at the Chevy dealership. This time we took it to the local dealership where we purchased the vehicle new in 2007. Again, we were told that this is NOT a known issue.

This latest repair: replace accelerator pedal and reprogram, replace drive belt and tensioner. $635.00 charge.

This is the third repair for the exact same series of error messages. Each time we've been told that this is not a known issue. Chevrolet has really dropped the ball on this issue.

FYI: the computer resets itself after starting and shutting off the engine three times. That's the only way I could actually drive the truck to the dealership. The check engine light was on but the error messages were gone and the engine had full power.

mmb617

I think my problem might be different from what most of you are having. For one thing my Yukon is AWD instead of the selectable 4WD I think the Tahoes have, so that may enter into the picture. I'm pretty sure my problem stems from something in the Stabiltrack system because if I lock that out by pushing the button on the dash it never has the loss of power problem. If I don't lock it out occasionally it won't want to accelerate from a slow roll. The computer seems to be pulling the power because it thinks I'm in a low traction condition. Other than when this happens the vehicle has great power so I think that rules out any actual engine problem, such as bad spark plugs, dirty throttle body, worn timing chain or anything of that nature.

I'm thinking it's a bad sensor somewhere but I don't want to just randomly start throwing parts at it. I'll have to get the codes pulled and see if that gives any indication.

Since I can lock out the stabiltrack system and not have any problem it's not urgent to me, but I know something is not right and it's not going to fix itself.