I've searched for several hours, and have found a lot of useful things to try to fix my problems, but need some specific help. Here's the problem -- intermitent and only occasional miss, loss of power, tach jumps ~300 rpm under load, ~500 rpm at idle, rough idle.

Replaced so far with no effect -- plugs, coil, ign. control module, cap and rotor.

Questions -- How do I test the pick-up coil, and if new plug wires don't help, any other ideas?

Oh yeah, it's an '88 SC with the 2.8 MPFI, recently replaced the ECM as well which was fried when the fuel pump shorted. The problems started about two weeks after that.

Thanks.

 

Search for my thread on rebuilding your distributor.
Just go get new one & rebuild the distributor.
OH you WILL NOT be wasting time.
You have to remove distb, pull the shaft outta distb assembly to replace it.
Meaning, it's the original one there.
Damn part is cheap, it PITA to do the job but so worth it!
Add to the list a new "O" Ring & ALSO GET a Small Block Chevy distributor base gasket.
Replace the "O" ring and before ya stick distb back in engine, slip onto shaft the SBC gasket, using a FILM of black RTV.
MAKE SURE the distb area is spotless (use white paper towels to make sure area clean). Using both gaskets will ensure a leak free job in the end.
It is a worthwhile project.
And then, plan on a new timing chain/tensionser/balancer snout sleeve, too. BIG PROJECT yes, but major gains in economy, cooling of engine & actully a bit more "ommph"! too!

PS by "testing it" the wires may be so fragile that you break them anyway. Plan on this job.

 

Thanks for the info.

 

Easy way to test the pick up coil is get a multi meter and do an Ohm's check. It sould be a very low reading.
I rebuilt mine I'm sure the thred is on here some where.
It's on my car my cardomain site .

 

Again, my point being that IF original Probably so, FRAGILE WIRES!
Plan on doing the job.
PS Visually ya can tell "how old it is" It looks heat/engine bay abused/damaged, cause they usually not replace due to distb. removal/disassembly.
Accept it as to be replaced and ya win with knowldge ya got that potential problem is solved for another what 10-15-20 years (1985-1992 cars)