Join Date: Mar 2012
Location: Newman Lake, WA
My apologies for missing this thread. It has been crazy busy here!
I'm glad you solved your line pressure problem. In short, yes, your EPC solenoid was stuck in the open position.
What you need to do with your current "no 4th gear" problem is to see if the PCM is indeed commanding a 3-4 shift. If it IS commanding a shift, yet no shift is occurring, that will be one set of things to check. If the PCM is never commanding the shift, well, that's a different diagnostic strategy altogether.
If your 2nd gear is solid then, most likely, your band is fine. The 4th gear portion of the band servo is a VERY simple mechanism and it is unlikely that anything is wrong with that. But, the possibility DOES exist. My suspicion is that the PCM is not commanding the shift for whatever reason...
1995 Camaro Z-28, M6, 396 stroker, Scat forged 3.875" crank, Scat Ultra Q-Lite 6" H-beams, Icon forged pistons (4.030"), splayed 4 bolt w/ARP studs, 12.25:1, AFR 210 heads (2.08"/1.6", 58cc), Comp Ultra Pro Magnum XD 1.7:1 rockers, GM847 cam (234/242 .611"/.632"), Edelbrock LT4 air-gap intake, Spec Stage 3+ clutch, Fidanza aluminum flywheel, 24x conversion, 0411 PCM, TPIS 58mm, Bosch III 42# injectors, Aeromotive 340, Kook's stepped LT's, Kook's custom stainless 3-1/2" merge ORY, Magnaflow