RPMs erratic and on/off, stalling?

SJBAUSLEY

MEMBER
2015 CHEVROLET IMPALA
2.5L
4 CYL
2WD
AUTOMATIC
100,000 MILES

I don’t even know where to start, this last week has been so stressful.
So, I started having issues with my car after brakes were computed. The first thing I noticed was the RPMs needle was not moving. Then I started to notice it was an on and off thing but when the RPMs needle isn’t working my car is performing horribly. It is driving horrible when I am trying to accelerate after being at a complete stop, it has cut off, and it is taking longer to start up.

I went to AutoZone and had the diagnostic test done. 1 last week when the issue started and one today after I had the crankshaft position sensor replaced.

I took it to up to shop today and he recommended crankshaft position sensor, it was changed but I’m still having the same issue and the code is still popping up.

See attached diagnostic test from AutoZone, 1 is before and after crankshaft position sensor replacement. The new one now shows a camshaft sensor code as well.

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
43,010 POSTS

I don't see the attachment? but it sounds like the BCM or the PCM might be going out. Also, I would do a CAN scan instead of a regulator engine 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

and

https://www.2carpros.com/articles/can-scan-controller-area-network-easy

Here is one for about $99.00 if you need it:

https://amzn.to/3ZixY4v

Let me know and I will give instructions on how to fix the problem.