Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
Hello everyone need some help! I have a 2011 Buick enclave 3.6 runs ruff on an idle seems to run smooth when you bring it above 1000 rpm's and higher has no dtc's I noticed that I have no cmp sensor rpm data it's at zero but all 4 cmp sensors display on my scanner and seem to be working correctly ...not sure where to go to fix the problem with all 4 cmp sensor working any input would be greatly appreciated
The cmp sensor data is active counter 0 to 255 shows and up and down wavelengths on exhust cam and intake cam bank 1 and bank2 but cmp sensor rpm shows zero I thought the ecm was using the cmp sensor active counter data to figure cmp rpm but with all 4 sensors working it's got me confused on where it's getting the value for cmp sensor rpm at...I haven't checked fuel trims but also noticed my engine load percent is at like 60 when idling thought that was funny too
That cam sensor rpm pid may not apply to the car you're working on. That's probably why it doesn't update even though you can see data from the 4 cam sensors .
I would ignore it.
I have another 2011 with the 3.6 and the cam sensor rpm pid shows data on it.. rpms pretty much match the crank rpm and I have 2008 that show the pid working when scanned also... from my understanding the system is using the crank and cam rpm to set the variable timing with no cmp rpm I feel that it's not adjusting the cam to the proper timing....going to tear down the top of the motor today to confirm the timing marks are where there supposed to be...it act's like the timing is advanced or retarded...but I don't understand why the cmp sensor rpm would go to zero from it jumping time
There is a bulletin from GM on the subject. It basically tells you to look for backing out terminals on the connectors. 2009-2014 virtually anything with a GM 3.6L engine is effected.
Topic Author
