If it were mine I would do a compression test, if its number 4 I believe you have sufficient room to get a tap in there and insert a heli coil if it comes to that. My last 3vzfe had a bad valve and compression was only slightly down, so it didnt have a obvious miss fire but was still lacking on power. I hope this is not your issue! Just trying to pass on some knowledge, best of luck to you!

 

Combined posts, see below.

 

Interestingly (this came up in another thread), my Hall sensor/signal generator in my distributor fails on a resistance test between both G1-G(-) and G2-G(-) by almost doubling the upper limit of good.

The NE-G(-) test passes.

I shot the time today too, and jumpered, it's at 10BTDC and jumper-out, it's at 8BTDC; both read at idle. The dot jumps around a little bit, but I have yet to determine if this is magnetic induction pollution (there is no place to clamp the #1 wire sufficiently away from other wires). It could also be that I have a fairly crappy Sears timing light.

I'm holding out hope that replacing the distributor fixes the remainder of the drivability gremlins.

How much does input to the ECM from the signal generator effect drivability?

At this point, my mileage sucks (11 or so in town) and there is not a whole lot of power between 2k and 3k rpms.