Reduced engine power....anyone have a stick of dynamite??

[tomloans]

Dorman M10-1.50 X 20MM hex bolt but you really only can fit a 10 mm length bolt. I had to use a bolt to occupy the space as noted in the video. If I can find a bolt that is about 10 mm, I am going to replace it.

 

[John Bragg]

Awesome thanks much appreciated

 

[tomloans]

This would probably work best....

https://www.ebay.com/itm/10-M10-1-5...AAOSwIUVcFRCM&frcectupt=true&autorefresh=true

I just ordered these as these are the shortest I can find.

 

[John Bragg]

Well the beloved Yukon is at it again reduced engine power over the weekend, then today after work no matter how many times I shut it down and restarted it reduced engine power codes pulled 2135 1515 0455 0171 and 0120 I believe the evap code has been there it has been coming and going for a while. Back to the drawing board it looks like ugh

 

[Erickk120]

That sucks, I sold a 6.0/4l80e express to some friends a few years ago, they had the same problem, when they got the message years later they threw a lot of parts at it and it didn't fix it. I'm not sure what it was, I believe they told me the tranny oil was mixing with the radiator or something similar and it made it go into reduced engine power, I will ask them and see if I can get better details.

 

[swathdiver]

Well the beloved Yukon is at it again reduced engine power over the weekend, then today after work no matter how many times I shut it down and restarted it reduced engine power codes pulled 2135 1515 0455 0171 and 0120 I believe the evap code has been there it has been coming and going for a while. Back to the drawing board it looks like ugh

Are the codes related to the throttle body, P2135 and P0120, the same codes you were getting before you replaced the old one? Are they new?

The P0120 is putting your engine into reduced power mode as the TP1 sensor voltages are off and not in sync with TP2. Get the shop manual for your truck and follow the trouble shooting guide. Unless you find a bad ground or loose wire, the problem is either the throttle body or ECM.

 

[John Bragg]

Are the codes related to the throttle body, P2135 and P0120, the same codes you were getting before you replaced the old one? Are they new?

The P0120 is putting your engine into reduced power mode as the TP1 sensor voltages are off and not in sync with TP2. Get the shop manual for your truck and follow the trouble shooting guide. Unless you find a bad ground or loose wire, the problem is either the throttle body or ECM.

I have replaced both the throttle body as well as the ECM the same codes have been an issue since it began about 2 years ago

 

[swathdiver]

I have replaced both the throttle body as well as the ECM the same codes have been an issue since it began about 2 years ago

Well, you have a wiring problem or either one or both of those is still no good.

 

[tomloans]

After I cleaned and regrounded the grounds behind the engine and also the grounds under the Chasis, It was good for nearly 4 months, then it came back. But this time, I only had one code, p2135.

Before I had P2135, P0220, P1515, and P1516. Obviously, I had bad grounds. I know i did because one was completely corroded and would certainly have had an issue

You have to make sure that the two grounds in the back of the engine are cleaned and grounded securely along with the drivers side chassis grounds then you can move on to replacing parts. I even went as far as grounding the chasis directly to the ground on the battery.

In my case I have ordered a new pedal sensor and will replace it. But you never know. I am as frustrated as you are. This is a crappy design. So annoying.

In your case you appear to have several issues. I have seen this many all at once on other forums when the passenger side ground has been disconnected. Did you properly ground this too.

I will let you know if the the pedal sensor solves my issue.

 

[live2pull]

I too am plagued with this issue. Why GM went to a computer controlled throttle is beyond me. Maybe a cable actuated throttle fails too often.

Of course, I did the Dorman TPS. (Mistake) and threw a connector and APPS at it. Still no luck. I recommend buying a Tech 2. Are they expensive for a diagnostic tool? Maybe. Depends on if you are going to be working on your vehicle long term. Eventually, they will pay for themselves in spades. I will be purchasing one when funds permit to tackle this issue.

Current plans to remedy this before Tech 2 purchase are;
New ACdelco TB, clean up engine and body grounds, see if the problem is fixed.

Well, you have a wiring problem or either one or both of those is still no good.

Could the TAC module be bad as well?