Hey Everybody,
I posted a couple months back with alll sorts of possible predictions as to why my truck would not idle correctly. After replaceing pretty much everything related to ignition and fuel, I took it to the dealer for them to run the PCM. The PCM was fine. I also asked them to correlate the crank sensor and the cam sensor because I kept getting that code to come up. But they said they couldn't do it because the timing was to far off. The problem was that everytime the tech reinstalled the distributor and started it, the distributor would be in a different place when he checked it again. Is this obviously the timing chain? or could it be more than that?

 

well of course it's going to be in a different location when he checks it again after he starts it. The engine has turned over, so the rotor is going to be pointing in a different direction. Is that what you were referring to? If so, the tech didn't know what he was doing or was just trying to screw you out of money. I would suggest you time it yourself so you can be sure whether it's your timing chain or not.

 

The tech set the engine to top dead center on comp stroke, then would put the distributor in with the rotor pointing to the "6". Then he would crank the engine over to see if that solved the problem. When it didnt solve the problem he turned the engine back to top dead center on comp stroke and took the distributor cap off to see that the rotor was not pointing to the "6" on the distributor anymore, its in a different spot.

 

The next step would be to pull apart the front of the motor to observe the timing marks on the cam/crank.

 

Ok i got the timing cover off and the marks line up perfectly the chain has a little bit of slack but nothing to where it could skip a tooth, which is really frustrating. Now where do i go from there? Pull the cam maybe its warped? get a used engine? any help would be great, im so lost
thanks

 

Has anyone checked the roll pin at the bottom of the distributor shaft? If the timing chain is good and the timing marks reliably line up, then the only other explanation is a problem with the distributor drive at the back of the cam. It could be a few missing teeth off the cam drive gear or a broken roll pin.