Have you ever had a splinter in your finger that you just couldn’t get out and it festered and hurt and pissed you off every time you moved that finger a certain way?
Well, last fall this Jeep started the random miss again so I quit driving it for fear of it running the other cylinders too lean since it’s TBI and tried to track it down. Could not figure it out and finally had to ease it to the barn for winter storage.
Over the winter it dumped a ton of trans fluid on the floor of the barn, but the B&M pan I put on was clean so I knew something was wrong with the rear output seal (which is actually in the quadratrac.)
I hadn’t managed to touch this thing all damn year, I just kept the battery charged and left it with the hood up, mocking me every time I went into the garage. Between the Postal’s issues and getting the JKU, there just hadn’t been time to pull the tcase and hunt down the miss more.
a couple weeks ago I read something about the tach signal adapter on an aftermarket efi causing someone problems, and I realized I’d never really eliminated it as a source because the Jeep clearly ran fine aside from the miss. I called FAST and they agreed, these going bad is all or nothing, the vehicle dies and won’t run, they don’t intermittently fail, though “anything is possible”.
this is a little electronic box that “cleans” the tach signal up into a clean square wave that the efi uses to know when to fire. It plugs into the harness and the tach prong on the HEI and gets a ground. I had a really good, clean ground to the head with toothed washers, but I went ahead and added a new direct battery ground to that spot and I got a factory-style connector for the HEI cap connection (I’d used a crimped female spade).
I pulled and redid the two seals on the front of the Quadratrac and reinstalled it while servicing and painting the rear driveshaft.
Took it for a drive yesterday and it seems to be cured. Running like a beast again and no signs of any miss. Only drips under the Jeep (I really needed to do the rear tcase output too, but had no interest getting in that far). Next year I may rebuild the original quadratrac I still have and swap it on.
So all of this left me feeling like I FINALLY got that nasty splinter out and I plan to drive the wheels off this thing between now and storage time.