Spark Issue..

New to the forum and at a loss.. looking for help..

93 350 ... having a spark issue that has me puzzled..

We get spark at the cap.. however only Cylinders 2 and 8 are getting consistent spark at the plug per the timing light.. all other cylinders are getting a random spark once every couple turns.. however if we pull for example the #1 and ground it to the block.. we get a consistent spark.. throw it back in the block and nothing.. replaced the wires and the cap today.. with no change.

Weak coil?

Ideas.. thanks in advance..

Update on the issue.. we have swapped everything but the distributor.. would that cause consistent spark on 2 and 8 and intermittant spark on the other cylinders?

Thanks in advance.

Might be the physical rotor inside the distrubtor. If you checked your timing belt, than that is where I would look next.

A bad magnet on the shaft, or slightly bent shaft.

//2000CAYukon

I had the same problem with my 88 ½ 350 chevy. I replaced everything under the hood except the distributor. This weekend I am going to replace it too. This improved the performance of the engine while at higher RPMs but it would die at idle. Come to find out…..Distributors themselves do go bad. There is a magnetic “Zone” on the shaft that actually provides an impulse to the “spider” wheel and tells the pick-up and the electronics in the ignition module to fire. Over time, this magnetic Zone looses strength and is unable to provide the proper pulse strength to fire the timing circuitry. The confusing thing about this, was it kept sending a “Timing” error code. Had to look past the symptom of timing to find the real cause.
PS- I would advise a New one rather that a Reman.