Seems to only happen when the car is warmed up, usually after driving at least 30 minutes, but when it starts acting up I'll get little flicks of the tach, maybe 200rpm, and then it feels like the engine just completely cuts out for a fraction of a second, often 3-4 times in rapid succession. Once it starts doing this, it's much more prominent when trying to accelerate, but even then isn't necessarily consistent, as it rarely acts up accelerating normally from a stop(but can act up a lot if trying to accelerate hard.) When it's between stumbles, it feels absolutely fine. If it does it when I'm braking and near stopping, it'll just stall, dropping off as if I switched the ignition off. Even just cruising down the freeway at 2500 rpm, it'll randomly do this. It seems most prominent on warm sunny days, which in California is most days, and seems to rarely do it at night. The car starts right up every time and idles smoothly, all the power is definitely there until it starts acting up. If it stalls from this issue, starting it back up is not an issue, but it does nothing to reset the clock on the issue presenting itself.

It's had a few running issues that needed solving, like it used to have a big stumble after the first start of the morning, and that turned out to be a bad ignition coil. I've got new wires, plugs, cap and rotor, injectors are newer and low mileage, fuel pump is new, and the TPS shows good voltage across the range, pickup coil tests good. The car had it's cat removed by the shop that installed the subframe links, they said it was in the way, and I'm not sure if the lack of cat could cause this issue due to wonky sensor input or not.

Has anyone had an issue like this? I've looked for damaged wires but not found any, not to say it couldn't still be that, but I'm kind of lost as far as what else to look at.

 

Ignition module or coil (even though it was replaced recently).

 

If the pickup coil you refer to is the ICM at the bottom of the dizzy. My Ignition Control Module was bad and the car would just randomly cut out. Would always fire back up and no rhyme or reason to when it would happen again.

 

Ah, forgot to mention the ICM was also replaced. The ignition coil was replaced in part in hopes of solving this issue, but it didn't make any difference. I don't see the new ignition coil having the exact same pattern of failure out of the box, I'd expect if it were a bad part that it'd either be not as bad as the one it replaced or worse.

 

Any codes? MAF sensors have been known to act up and cause poor running conditions at times

 

I did see the check engine light come on once in the past few months, but it was just for a couple seconds and it wasn't actually misbehaving at all when it did pop up. When I got the car stopped, there were no codes and no light. That's been the only time.

 

The ECM will store the code. You can do a search here on how to jump the ECM and it will flash the stored code/s. Even though it did not happen when the car was running poorly it will at least give you a starting point on where to look.

 

Check the code(s) and also ohm test the pickup coil in distributor.
which brand coil and icm did you use?

 

The car has had 3 new ICM's(1 Duralast and 2 AC Delco,) and all of them have failed with the first drive. What the hell, man?! What am I supposed to do with this thing? Are these ICM's going to keep failing immediately over and over?

I don't recall the brand for the ignition coil.

 

Are you using the correct grease under the new ICM? Overheating for lack of correct grease will kill them. They usually come with a small packet.