Still working on my friends '97 4x4 4.3 Blazer. We replaced the motor with a used one. Do we need to do a crank sensor relearn or a cam sensor adjustment? We keep getting a P0340 code from the OBD II.
Any help is appreciated.

 

i dont believe there is an adjustment on the cam sensor.

 

P0340 - Camshaft Position Sensor A Circuit (Bank 1 or single sensor)

This is not a code indicating that there is a problem with the CKP/CMP correlation value. that would be P1345. This indicates that there is an issue somewhere in the CMP sensor circuit. You should be able to check over the wiring with a multimeter to make sure that there are no intermittent drop outs in continuity from the CMP sensor to the PCM.

 

Did you pinch the wires between the bell housing and the block for the camshaft sensor. It will throw this code.

 

The wires between the CMP and VCM seem fine. They weren't pinched in the process of attaching the motor to the transmission although I have heard of that. The plug at the CMP has voltage to the pink wire. The ground is good and there's continuity back to the VCM. Do I need to untape/ unloom the wires and check them? Should I run jumpers from the CMP to the VCM to see if it is the wires? Should I tell my friend to drive it off a cliff into the ocean?

 

Eather way i think you still need a relearn, unless you are using the ecm out of the donor truck.

 

So what is a relearn and how do you do it?

 

Take it to a dealer or a shop with at least a scan II diganostic tool. Some dealers will do it for free some will charge at least 100 dollars. It is not really something you can do yourself with out that tool.