Originally Posted by Lignite

Thanks for the tips. I'm a bit worried about my wideband O2 sensors as well (2 of them, other 2 postcat sensors are eliminated in the ECM tune) but from reading up on them and some bumbling testing I think(?) that the O2's are functioning correctly.

I haven't made much progress yet, as I've had some major breakdowns in the interim (swapped out 7.5" rear end for 8.8", chevy rear springs, front wheel bearings, Warn Jeep hubs, brakes, all in my yard and its been COLD).

But, before the breakdowns, I decided that the miss was getting worse, and that I may (or may not) be wrong about the A/F not richening. I think now (but can't confirm until I get back on the road) that the reason I'm not richening under boost is that the engine is not actually 'getting wound up' (or approaching WOT) before I get spooked and let off because of the missing. So while it is dangerous that I'm not getting more fuel, I'm not pushing the motor very hard (chickening out) because of the miss, and never get close enought to WOT to throw more fuel in. So if I can find whats causing the miss, I think it might fix my A/F problem.

Among the other things I've changed since starting this thread, I have switched the DPFE (no better). I did get new plug wires, but don't believe the old ones are bad (aftermarket 8mm motorcrafts) so haven't installed them. I have also installed a new pair of aftermarket coils, but can't test them until I get the front and rear ends together (soon I hope!?!)

Thank you again for the advice.

P.S. checked 2 plugs some time ago, looked good to me (but I'm far from an expert). I also got a scanner, but haven't learned how to read what I'm seeing yet (no codes thrown).