I need some help on this one. I have a hesitation issue between 1400 ~ 1900 rpms thru every gear. Slight backfire when I rev it up. Ran codes - Code 55. I just finished eliminating the PTU (I had a spare good one and replaced it.) The coil packs are all at .7 ohms. The injectors all new and ~ 12.2 ohm. I tested the harness at the ECU. again, 12.2 ohms on all injectors. New spark plugs installed - gapped to .035. Type - PFR5B-11B. Conducted "Auto Balance Test" with Conzult. #4 cylinder rpm drop is out of range. Tested over a dozen times. Same result. Manually dropped #4 cylinder, it takes a few seconds for it to come back. All other cylinders recover very quickly. Pulled #4 injector, checked O rings, good. Checked ALL spark plugs - good. I have had my JWT ECU since 2003. Anyone ever had an ECU go bad just on one cylinder? Or am I missing something? TIA.
Follow Ups
OK TT.Net Gurus, could my ECU be going or what? - 91z tt10:27:41 06/11/11
