So I finally got my new Thompson Motorsports engine installed, Its a 5.3 bored to a 5.7. everything went good installing the motor, started It up and right away and idled at 1500rpm and will not come down then i get a p0342 cam position low voltage code. I order a new sensor and put it in, It does the same thing so I check all my grounds and check continuity on my cam sensor wires and everything is good. the old motor ran fine until I sun a rod bearing, I have no clue what to look for or where to go from here. Any help from you guys would be great. Thanks

 

check the pins on the female connector, one might spread/pushed back...

 

I had the exact same code after a cam swap...turned out the connector at the front side of the passenger head was unplugged lol, it's in the same bundle as egr plug

 

I have checked everything with the wiring and everything is good I just don't know what else it could be. It ran fine in the old motor. I'm about to go nuts!

 

You might have bumped/damaged the cam sensor if a different cam got installed

 

I installed the cam before the sensor was put in and I have also put a new sensor in it.Its at a dealer now and their telling me they can't find the reason its not reading the reluctor wheel on the cam. This sucks, brand new motor and one sensor is screwing the whole thing.

 

It sounds to me like the spacing between the sensor is incorrect...I would pull the sensor and see if it was either too close (rub marks on sensor) and if not its probably too far way in which case you will have to do something to drop the sensor down further...I would hope it was too close then you can just shim it away from reluctor wheel

 

Did you swap the two wires in the cam sensor to convert from gen4 to gen4 at the same time you moved the sensor from the back of the block to the timing cover?

 

The cam sensor is still at the back of the block its at the dealer now and there trying to put a spacer under the sensor if that dose not work I'm going to pick it up. The sensors have no damage from rubbing, how could I set the sensor lower to see If that will work.

 

If I can't get this working I'm going to have to take it to an electrical automotive shop an they charge $70/hr so I'm trying to avoid that at all cost.

 

What camshaft are you using? Is it the same cam that was in the old motor?

 

Yes it is the same cam that was in the old motor.

 

Finally got it, put a .28 shim under the sensor. Runs like a champ, thanks for your guys input.

 

Great, I was going suggest you measure the old engine spacing and compare them.