Hello, I have a 1993, 5.8l, f-250, truck seems to run great. but with the exception at anything but idle it makes a clicking sound. The truck is in park and with a light tap of the throttle starts to tick and increases with rpm and then stops as rpm decreases. Problem is odd as I have taken a stethascope to every corner of the motor possible and I get no clicking. I have taken off the spark plug wire on the left rear as viewed standing in front of the motor. back of the motor and the problem stops. Do you have any thoughts? Thanks for your help

 

I have taken off the spark plug wire on the left rear as viewed standing in front of the motor. back of the motor and the problem stops.

You saying it completely stops if you take that plug wire off? Sounds like cross firing between cylinders.

Either that or you have a bad wire shorting to the engine, take it to a place that gets completely dark. Open the hood and watch it at an idle and while you throttle it up a tad, if you see fireworks you need new plug wires.

 

Thanks Dan, since reading this I have read more about crossfiring. I didnt even no that was possible. You would think the insulations would be capable of stopping that but guess not. This must be an induced voltage onto the other wire. I guess better seperation for the cables would be good. The wires are fairly new maybe 6k miles. I cant remember when I started hearing the noise. I will try to isolate wires later when I get back into town later next week. Thanks again.

 

I get a clicking sound at warm idle from the same area (pass side rear of engine #4 cyl). It is intermittent. Wires are routed correctly.
Did u resolve your issue?

 

Sure did, It was a leaking exhaust manifold gasket. I was able to find it by taking a vacuum and taping it to the exhaust pipe and setting it to blow, huge leak around block specifically around the #4 cylinder. No clicking ever since
Jerry

 

Thanks, mine is not exhaust, it very intermittent. I'm worried it's a lifter sticking.