Hi all,
Would like some help diagnosing or at least theorizing possible causes for an engine stumble / patch of rough running which lasts from 1800-2200 (approximately) rpms only in 3rd gear. This issue has been going on for several years.
I have an H55f transmission and the original 3FE. I've done the usual items such as spark plugs, wires, rotor, cap, O2 sensors, rebuilt fuel injectors, new fuel filter. No check engine codes. MAF has been replaced with a new (used) unit. TPS (new oem) has also been replaced and calibrated- although perhaps I should check it again. FPR was replaced with a new unit, but it was defective--so the old one was put back in. Valves have been adjusted.
In all other gears and RPM ranges, the engine runs smoothly. However, it is noticeably rough in the exact situation described above. Any ideas, comments on general theoretical causes, or thoughts are appreciated.
Thanks.
Would like some help diagnosing or at least theorizing possible causes for an engine stumble / patch of rough running which lasts from 1800-2200 (approximately) rpms only in 3rd gear. This issue has been going on for several years.
I have an H55f transmission and the original 3FE. I've done the usual items such as spark plugs, wires, rotor, cap, O2 sensors, rebuilt fuel injectors, new fuel filter. No check engine codes. MAF has been replaced with a new (used) unit. TPS (new oem) has also been replaced and calibrated- although perhaps I should check it again. FPR was replaced with a new unit, but it was defective--so the old one was put back in. Valves have been adjusted.
In all other gears and RPM ranges, the engine runs smoothly. However, it is noticeably rough in the exact situation described above. Any ideas, comments on general theoretical causes, or thoughts are appreciated.
Thanks.
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