Newton06

Camshaft position sensor. Sometimes the car will be hard to start (crank for a few seconds). After I abort the start, and retry, it will usually start right away, followed by the CEL. Sometimes it wants to stall if the vehicle has just been started, but no CEL.

At first I thought it may be a tune issue, but it happens randomly so I took it to Autozone for a readout.

2005 C6 Z51 6-speed with 73k miles.

Should I just replace the cam position sensor? I have no idea where it is even located.

Thanks.

truckplay

has the car had any engine work ? it could be unplugged if not you need to slide it out and check for damage. some timing gears get loose and damage the sensor. DO NOT DRIVE IT UNTIL YOU MAKE SURE THE GEAR IS NOT LOOSE.

Newton06

Yes, Lingenfelter heads & CAI, Comp Cam, Fast Intake, Kooks long tubes, etc...

This has been going on at least since summer.

I just got it back from the body shop last night (friends spun it out & went into a ditch). They had to replace the front radiator, AC cooler, oil cooler & lines, etc.

truckplay

the cam sensor has a pigtail extension. 1 end plugs into the sensor, behind the water pump and the other end is over the front leaf spring. I bet 1 is unplugged.

Newton06

Yes!

Looks like one plug is disconnected. I will try to see if I can get it inserted by snaking my hand down there.

Thanks!

Complete Street

For what it's worth...

Others with this problem may need to just replace their cam position sensor. I've seen older ones have problems reading double roller timing chains in particular, but that is extremely rare - probably only 1 out of 50 installs will see this.

And if that doesn't fix the problem, the next step would be to check the cam sprocket. I've seen installs where the customer installed an LS1 cam sprocket (which has no signal reference) on an LS2 car.

Andrew