Crankshaft Position sensor replacement

Gr1m · 08-20-2010, 09:29 PM

Hey guys i was having problems the other day with my car stalling out and backfeeding power all over the place. After i got that resolved i ran into other problems.

the original problem was a corroded line running from the positive battery terminal to the main fusebox under the hood. It was only giving my car about 5.5v instead of the normal 12v. i resolved that problem.

after starting it up and driving it home from where i had stalled out, an SES light came on so i stopped at autozone to get the code read. P1374 which is a crankshaft position sensor (CKP) code. I just finished installing the new one, reset the codes in my car but it is still stalling, having a hard time starting and also very hesitant throttle under 2.5k rpms.

Ive heard you need to go to a dealership and get a crank position relearn (AKA CASE relearn) but i am just wondering if this is true?

Ive also checked my coilpacks (as that is also a possibility for the P1374 code) and they are all 6.4-6.8 (which is in range of being considered good)

I drove the car to go fill it up with gas after i reset the codes and the code did not come up again for the 5 or 10 minutes i had the car running (it also stalled 4 times on me) so im wondering if i just need a CASE relearn to fix the problems.

i need to check my plug wires tomorrow, but any other ideas on what it could be? im more inclined to believe that it is an ignition problem because i had my fuel pump replaced under 25k miles ago along with the fuel filter. im pretty sure i checked all my fuses but i will also double check them tomorrow as well.

hoping cliff or another GM guru can chime in here, thanks everyone and sorry to richie for busting his balls the last 2 days lol!

Cliff8928 · 08-21-2010, 01:38 AM

Check that your plug wires or coils aren't arcing on anything. Also check the crank sensor harness. It's a little harness all by itself that runs from the ignition module pretty well straight down to the crank sensor.

Gr1m · 08-21-2010, 09:14 PM

ok guys i replaced the 24x and the 7x crank position sensors and the car is still stalling and running rough, its throwing another SES code so i will check that tomorrow and see what the deal is with that. all my coils and wires seem to be within the operating ohm levels so im just wondering what else could cause very hard startups, misfires, hesitation and stalling under 3k rpms?

Gr1m · 08-22-2010, 11:37 PM

got it fixed after hours of testing connections and combinations of un/plugging the 24x/7x crank sensors to see which would stall out the car and at what times. came to the conclusion that the PCM is bad. the car was throwing a repeated P1374 after we would clear it and then randomly either immediately pop up again or not show up but the car would still stall. i put the factory PCM back into the car and everything works great now, just lost my tune from the other PCM though which kind of sucks for now., looking into getting a HPT though.