Reduced engine power without cel

[Stage2Tahoe]

I've been thinking throttle body but you know how throwing money at a problem is......I can make the "rep" happen sometimes with it still in park by just blipping the throttle and it seems to me like it takes too long to idle down after it's been rev'd up. Like maybe the throttle body is too slow or is this normal?

I had to throw money at mine to figure it out. Everything I researched said it was the TCM. I started with that and it lasted a week. Then it started kicking codes more frequently. So I replaced the TPS. Then it went crazy and I had to leave my scanner hooked up to delete the code to get home from a baseball tournament 12 times in 34 miles. My Tahoe couldn’t drop below 1000 rpm. I found that when I replaced a week area in the circuit it would show another week point. I suggest taking the intake tube off and starting the engine. Look to see if the butterfly is fluttering at idle. If it’s fluttering then it’s possibly the driver in the throttle body. It sucks but this is the world we live in. It’s a money maker for the auto manufacturers if something goes out.

 

[travstick]

Well.... still have my rep issue. Replac
ed throttle body this eve, it does idle better and seems more responsive but still goes into reduced engine power without a check engine light or dtc . The ONLY time it does it is when I'm sitting still and go on the gas hard. Sometimes I can even be in park and blip the throttle fast and aggressive and it'll rep...... thanks to everyone that has replied.

 

[wjburken]

Well.... still have my rep issue. Replac
ed throttle body this eve, it does idle better and seems more responsive but still goes into reduced engine power without a check engine light or dtc . The ONLY time it does it is when I'm sitting still and go on the gas hard. Sometimes I can even be in park and blip the throttle fast and aggressive and it'll rep...... thanks to everyone that has replied.

It might be the Accelerator Position Sensor. Have you tracked the APS vs TPS on a scan tool? If they get out of sync, it can cause an issue. Had a 2012 Impala do what you’re describing and it was the Accelerator Position Sensor, not the Throttle Position Sensor.

 

[travstick]

It might be the Accelerator Position Sensor. Have you tracked the APS vs TPS on a scan tool? If they get out of sync, it can cause an issue. Had a 2012 Impala do what you’re describing and it was the Accelerator Position Sensor, not the Throttle Position Sensor.

I've looked at it and watched it on live data and the % don't match perfectly but they do change in relation to one another together. Any idea how much they can differ and still be normal?

 

[travstick]

I've looked at it and watched it on live data and the % don't match perfectly but they do change in relation to one another together. Any idea how much they can differ and still be normal?

UPDATE!!! I still have the same issue but I have discovered that when I go into "reduced engine power" that it is throwing a ABS code- c0242-00. I've done some research and seems everybody that's had that code had a totally different cause of it...... can anyone tell me if the c0242 is the cause of my reduced engine power or is the code a result of the "rep"? I really don't want to go to dealer because I have 0% confidence in any of my local dealers being able to fix it without just flipping a coin and replacing parts till they find it, thousands of dollars later.......

 

[Mighty Hd]

I had this issue with my 2013. I eventually gave up and traded it as neither high, nor any local dealer could figure out what was wrong with it. It just came out of the blue.