2009 prostar isx crankshaft sensor issue

[Zmcd]

(01-03-2025 )Notch Wrote:  

(01-03-2025 )Zmcd Wrote:  My truck has been at a shop for 5 weeks now. A different shop, not the one that drilled the crank sensor out. After replacing the ecm, and engine harness the issue is gone. The truck runs normal as far as the motor goes. It runs smooth without erratic rpm changes. I’m now having a different issue I will make another post for. I know for a fact the tone ring is damaged, I saw where it got drilled thru. Teeth are still there, just damaged or chipped at one corner. But truck seems to be running good now.

It sounds like there is probably enough of the tooth left on the damaged one/s that the crankshaft position sensor is still able to pick it up and output a reference pulse to the ECM. Which would make sense being a hall effect sensor and not a VR sensor, but that's a whole other topic... Glad to hear that part of your issue is resolved.

And as a note, my experience has been that original crankshaft position sensors always seem to be a pain to remove on these. I will unbolt them and then turn them as much as I can back and forth to try and break them free in the bore before trying to pull them out. And worst case if they break apart when trying to pull them out, I will run a wood screw/self tapping screw into them and pull on the screw.

It was drilled thru on the last tooth and the larger tooth or flat surface. I’m just glad I didn’t have to try and replace that just yet. Now I’m having an issue with the truck shutting off when the abs turns on. Loses power for about 5 seconds and then gets back to it. Not sure what is causing that.

[Notch]

Did this new issue only start occuring only after the ECM was replaced?

[Zmcd]

(01-03-2025 )Notch Wrote:  Did this new issue only start occuring only after the ECM was replaced?

Well the truck was also DPF deleted on top of new ECM and engine harness. Mechanics are claiming they need to reprogram BCM which we’re going to try tomorrow. But yes, this did not happen with the other issue or old ecm.

[Notch]

I've seen a similar issue and without getting into specifics can say that there are torque reduction requests that can be made by the ABS module to the ECM that can reduce power based on things like the lean angle of a truck through a turn at a given speed. And that these parameters are not always set properly when changing programs. Either way, it sounds like you should really pull your file and have it reviewed before spending any more time or money looking elsewhere for a problem that has stemmed from the one major thing you've changed.

[Rawze]

(01-03-2025 )Zmcd Wrote:  ...
Well the truck was also DPF deleted on top of new ECM and engine harness. Mechanics are claiming they need to reprogram BCM which we’re going to try tomorrow. But yes, this did not happen with the other issue or old ecm.

also need to copy the program out of the ecm and emailed over to me to have it properly reviewed. No sense in tearing up, or shortening the life of the engine with a bad delete.