4.3 L Engine Codes

[blacksierra01]

Hi, I have a 2001 GMC sierra 4x4, it has the 4.3 v6 engine, i have had the check engine light on since i bought it 2 years ago, it was only a small evap leak back then. the truck has about 214 000 miles on it, now I am getting a P1345 code, cam/crank pos sensor corelation. I checked the distributer for play and there wasnt any. The truck still works good but is brutal on fuel. I was wondering if this sounds like a timing chain wear problem. The truck also has leaking intake gaskets, just a slow leak. Is there any way to check the timing chain for play without removing the front cover and with all these problems on a high milage truck,which is still in great shape body wise, do you thing an engine rebuild would be worthit or is it better to just fix these two problems with the engine in the frame as it works great other than poor fuel economy and the codes. Thanks,

[233monte]

You will need a scanner for this to check what the cam position sensor reads.more than + or - 2degrees sets the code. As far as checking the timing chain slop, it sill be tough on this one because their is no timing marks. With that many miles it's possible the timing chain is sloppy. Did you grab the rotor and see if it spins? That's a problem I have seen on these engines. Again, if you need a new distributor you will need a scanner to set/check timing.

[Zembonez]

Crank position sensor is a fairly common failure with higher miles. Replacement isn;t terribly hard. You'll need a crank relearn procedure once it's done. If the engine has good compression and isn't using much oil, I'd do the intake gasket and drive it.

[blacksierra01]

If the crank sensor is bad will the truck still run? I was told that a bad crank sensor results in a no start condition, but i dont know how reliable that info is.

the rotor spins , when i took the cap off and turn the rotor by hand, you can feel it turn up the face of the gear. i have not removed the distributer from the block