Throttle position sensor correlation

[John Bragg]

My 2003 Yukon XL had a check engine light. It has had some starting issues doesn't always fire on first crank attempt. Had the codes pulled came up as MAF so I replaced it. Seemed to be better for a short time. Now starting issue continues and I have been getting reduced engine power. Started here and there now it is getting quite consistent. If I pull over shut it down and let it sit a minute start it up and it will be fine. Got codes pulled again now I'm getting throttle position sensor correlation codes. I have checked the wires and connections at the throttle body and the accelerator pedal. Both are clean and tight. No signs of moisture or bent pins or loose wires in the plug. What should the next step be...don't wanna drop a small fortune replacing parts. Going on vacation in a month and really would like to have it fixed before then. Any advise and help would be greatly appreciated. Thank you in advance.

 

[drakon543]

The tps returns a slightly different reading to the ecm depending on where the throttle is at. They can fail entirely and just be dead. They can lose segments so at certain throttle ranges it will send faulty signals or nothing at all. Or the dumbest one i hate the ecm will lose the tps home position for various reasons.

 

[ISU-152]

Now that you have the codes pulled you might try removing the negative wire on your battery for 5 minutes. This will reset all the codes and make your truck start a new ie. Idle relearn.

May or may not work but it's a free guess.

 

[fire730]

Is the throttle body clean on the inside?

Its possible that the pedal sensor is showing 0 and the tps is showing something different because the throttle plate cannot set in the position it wants to because its dirty.

 

[John Bragg]

Thanks for the tips I disconnected the battery and tried that we will see how it goes...I'll check the throttle body for dirt next that's a good point

 

[Rocket Man]

I had similar issues and codes and it turned out to be clogged cats. It showed as TPS code, MAF code, had reduced engine power, then codes for multiple cylinder misfires. If I shut it off and let it sit it would run great again for awhile until it warmed up the cats again. Have them checked for restriction. If your engine can't push out the exhaust it will show as multiple problems intake, firing, TPS, etc.