Reduced Engine Power?

2007 GMC SIERRA

300,000 MILES • 8.0L • 6 CYL • 2WD • AUTOMATIC

WANDA JOE DANE

MEMBER
1 POST

We’ve replaced the TBS, TB, Pedal, pigtail and we’re still having problems with reduced engine power. It’ll run right for a minute and hit limp mode. We’ve noticed the radiator fan doesn’t work and it came on once but that was it, we tested all of the fuses and they all work.

Aug 6, 2023 at 11:35 AM

STRAILER

✓Experienced Mechanic
55,561 POSTS

This sounds like the BCM or PCM is going out, but to be sure we need to do a CAN scan, you can get a CAN scanner (Controller Area Network) which will work on most cars from Amazon.

Here is a video to show you how:

https://youtu.be/u-4syLc-ifQ

Here is how to change the BCM out in case a code comes up for it, you can get a preprogrammed unit by searching Google or Ebay.

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