General LSX Automobile Discussion - New Motor Problems!

The vehicle in question is a 2005 GTO

Okay, so I finally got my motor assembled and installed this morning. (Pulled an all-nighter, as of this post I've been awake for 36 hrs)

The motor is a 110k mile LS2 rebuild with all new bearings (rod, main, cam), a very mild cam, valve springs, and an aftermarket double-roller timing set.

I'm having the following issues and could use some experienced troubleshooting.

1. The car has a difficult time starting, sometimes I have to crank it for 10-15 seconds before it will finally start.

2. While driving, I can feel the motor 'missing', almost like a loss of power for a fraction of a second.

3. The starter is having intermittent issues turning the motor over, sometimes it can't turn the motor over at all like it's got a dead battery, but I can crank it 30 seconds later and it'll work fine.


I'm throwing codes P0340 (CMP Circuit Malfunction) & P0341 (CMP Circuit Range/Performance). Anybody have any experience with these issues?

Really need to get this vehicle back on the road ASAP!

almost all of those issues can be attributed to a bad cam position sensor or a disconnected one.

Bump.

Thanks, anyone else?

could it be a timing issue?? is it only hard to start when its hot?

could it be a timing issue?? is it only hard to start when its hot?

Yes it does seem to be an issue when hot

is it tuned? sounds like that could be a problem as well

I have HP tuners, but my start/run issues seem to be cam sensor related.

Tonight ill be troubleshooting the sensor and replacing all the front seals

true.. the codes usually dont lie. could it be wiring for the sensor

almost all of those issues can be attributed to a bad cam position sensor or a disconnected one.

This.

bad fpr

I pulled the intake, radiator, water pump, crank bolt, crank pulley, timing cover today because i had a leak where the cover meets the oil pan. While I had it off, I checked the cam timing quick just cause.

I RTVed the timing over at the oil pan because thats where my leak occured. I pulled the cam sensor out, it looks okay, but it definitely also looks like it has some small scratches on the surface. I tried shimming it out a little, but that did nothing, I'm going to try a new sensor