P0336 Engine Code What’s Causing It

I have a P0336 engine code. My vehicle is a 2004 Chevy Venture van (3.4L V6 FWD). I had this code diagnosed and it pointed to a bad crankshaft positon sensor. The van has two of these sensors. I had both replaced with aftermarket parts (non oem). After this service was done, I am still having this same code coming back. The symptoms are these: rough idling, what seems like intermittent misfire, when I put the van in reverse gear, the misfire is far more noticeable. So much so that sometimes, the engine will stall in reverse gear. It has never stalled in drive gear but there still is a bit of misfire at idle or even at highway speeds. Both sensors have been changed and code cleared only to come back to same code after service. Any idea what’s causing this? Thanks in advance.
The sensors were installed at Canadian Tire. I did not tell them to diagnose the problem but just change the sensors as I knew ahead of time they were bad from reading the DTC.
Im not sure if the new sensor is or is not installed correctly. My symptoms on the van are still the same as before the installation. If the sensor is bad, why does it not give me misfires in Drive gear (well, not as much anyway) versus the reverse gear. The reverse is where the misfire becomes really noticeable.
Also, is there a way to test the theory that i have a bad crank sensor at the flywheel? I do have a windows based DTC scanner that can minotor live data. Can this be used in some way to know for sure that a wiring harness may be the culprit?
I have tried to wiggle the wire for the 24x sensor (i believe this is the A sensor, the one behind the balancer) but have not yet tried this with the 7x or the B sensor. I don’t think my scanner has an actual crank sensor monitor, can i just monitor the engine rpm to test the crank sensor? My code i got is showing the 24x sensor is the bad one. The wires for it seems to be ok. Wow, i wish i could discuss this in a thread or a forum.
I should also had that since the two sensors were changed, a CASE relearn has not been performed yet. I am not getting any code telling me a CASE relearn is required.

Answers for The Question

  1. Kyle
  2. mike d