Guru input needed!

[Rollin]

I have a problem that is running me ragged. I'm usually on top of things when it comes to these cars but this problem is making me pull my hair out bordering on breaking out the plasma cutter.
Here it is: I can set the cam sensor as per spec, and about 10 miles down the road it'll start sputtering and dropping cylinders until it finally dies and has a hard crank. I can get out move the cam sensor till the hard crank goes away and get it running again. I can get it to were the hesitation on rev is gone by ear tighten the cam sensor down and be off....... only for it to happen again on down the road. Bare in mind the car when is running right runs great. It just seems my cam sensor has a mind of its own. Funny thing is this is the 3rd cam sensor the tab has been in place on all three, the caps are good no cracks, the shaft play is good. Background on motor fresh rebuild, new timing chain & tensioner. Again when cam sensor seems set right the car flies that is until it needs to be moved once its running I can unplug the cam sensor unfortunately I'm running a Thrasher 92 so that fix works barely that is until the signal decays then I'm back to square one on the side of the road dead. Anybody run accross this type of a problem?????? Input needed... thanks. Geoff

 

[FJM568]

Are you talking about the caps or the whole assembly being replaced??? If it is losing it's position, I would check...
1) That the cup with the window is secure to the shaft of the assembly and if it is,

2) that the roll pin that holds the cam drive gear on the assembly isn't sheared allowing the gear to slightly rotate around the shaft...

Oh yeah, btw, I'm not a guru...but I play one on TV

 

[Nick Micale]

You might want to check that the balancer bolt or balancer has not loosened. Also check the interupter wheel pressed onto the back of the balancer to be sure it is not moving either.

 

[TurboJim]

Do you have a HV oil pump setup? Are you using thick oil? I've seen binding oil pumps damage the roll pin on the cam sensor and distributor shafts on MANY cars. If its easier to break the pin than turn the oil pump such will be the case. I would pull out the cam sensor drive and inspect to make sure the gear isnt turning on the shaft. Also, like Nick says, check the balancer

 

[arista5]

When you start having the problem was the cam sensor out of place (did you recheck it?)

this is just a shot in the dark but something i would try if i was pulling out my hair, can you try changing the Ign Module/pack oh narrow it to each one once.

I could be wrong but the Module gets the signal from the sensor and sends out the signal to the coil pack, if the module or pack is getting heated and screwing up the signal it could appear to be a sensor and when you adjust it you might be making up the slack in the module/pack (per say) Are you using AC Delco, or aftermarket Cam Sensors?


(i am not sure if it would still experience the same if you unplug the cam sensor but again i was guessing using common sense and what i can vaguely remember from hear/say)

 

[Reggie West]

Wait a minute. I thought the cam sensor is what starts the car and the crank sensor is what keeps it going.

The crank sensor is what trips the coil pack not the cam sensor.

Am I wrong here?

 

[Rollin]

Thanks for the heads up guys. I'll give it a look when I get home.