Hey all,

1976 Cutlass w/ 350.... I did major mechanical restoration over the past year - generally running well but yesterday was driving about 30 mph and engine lost power, then died. Idiot lights came on. Started right back up and kept going. Then after another ~20 miles I was accelerating away from a light and same thing, engine lost power... but then got it back without needing a restart.

So intermittently engine goes bye-bye.. I assume this is likely ignition related as a fuel problem wouldn't be intermittent like this ? (it has original GM HEI - I did recently replace all the original ignition parts with Ecklin parts from NAPA (they used to be high quality in the 80's. Ha Ha.).

Thoughts on where to begin? I just bought an NOS hei module on ebay - considering replacing that as a starting point - not sure if those tend to fail intermittently?

Thanks!

 

I would look for a loose wire some ware.

 

I agree with 442Harv.

I would go over everything you came in contact with on the overall mechanical restoration. May have worked initially but something could of gotten loose over time that was not ideally secured.

They can be fickle.

This from BlueCalais79s recent HEI issue thread.
https://classicoldsmobile.com/forums...es-hei-186753/

 

Was the pole piece in the distributor replaced?

 

Pole piece? No I don't think so - what is the pole piece?

 

It is in the distributor and is sometimes referred to as a pickup coil. Pull the cap and look at the bottom center of the shaft, it is there with two wires going to it from the module OE wires were green and white. With the car parked where it doesn't matter if it won't start, wiggle/tug those two wires at the pickup coil to see if they break loose. If the wire condition is ok unplug it from the module and test it with a multimeter it should be 500-1500 ohms and wiggle the wires during the test.

Another method to check it is to drive it with the vacuum advance disconnected, if the problem goes away it's the two wires. Disconnecting the vacuum advance stops the plate from moving in the distributor and keeps the wires stationary.

Chances of it being the pole piece are a little low but since most other things have been replaced it is worth a look.

The big IF is our assumption that it is spark but I agree with you the symptoms point to spark as the problem. If it does it again try to check it for spark or fuel.

 

Thanks for the detailed suggestions! I tested with a multi meter and it read 836.... steady when moving the wires - so they seem ok.

I did find a couple of loose bolts. The bolt for the condenser bracket was loose (condenser would move a little), so I tightened it up. Difficult to tighten, screw wants to strip... but anyway it is tighter. Also one of the bolts on the outside of the cap that holds down the coil? was loose... so tightened that up also. Hopefully it was one of those.

Will take it on a test ride in the next day or two to see if its improved.

Thanks again for the suggestions.