02-01-2010, 02:17 AM
I've got a 6-spd 93 with a bone-stock motor, electronics, intake and exhaust -
Over the past 2 years, the idle quality has steadily degraded to the point where it misses consistently now. I can see the headlights vibrating when extended, door panels rattle a bit, etc. There is no RPM hunting, and its totally consistent, except for being ever so slightly worse when cold. One cyl perhaps? Anything that loads the engine makes it worse (A/C, electrical load, etc). If I raise the rpms, it improves up to above 1400, where the miss appears to be totally gone. There seems to be an accompanying loss of torque below 2k rpms during normal driving but this could be my imagination. The car runs excellently at higher rpms and throttle settings with no hesitations, and it pulls cleanly to redline. No codes the last time I checked, but will check again. Emissions numbers were very clean, although the problem has worsened since the last smog check 9 months ago.
Recently replaced with no change in symptoms: injectors sent out and cleaned, plugs, cap&rotor, wires, 02 in front of cat, cleaned MAF. Compressions are even, across the board. Coolant usage: over 3 years or so, it appears to have lost a smidge.
Any ideas and thanks for help! If necessary, I would be willing to try a socal shop for diagnosis, but thats a 3+ hr drive for me/ea way.
-Jim
Over the past 2 years, the idle quality has steadily degraded to the point where it misses consistently now. I can see the headlights vibrating when extended, door panels rattle a bit, etc. There is no RPM hunting, and its totally consistent, except for being ever so slightly worse when cold. One cyl perhaps? Anything that loads the engine makes it worse (A/C, electrical load, etc). If I raise the rpms, it improves up to above 1400, where the miss appears to be totally gone. There seems to be an accompanying loss of torque below 2k rpms during normal driving but this could be my imagination. The car runs excellently at higher rpms and throttle settings with no hesitations, and it pulls cleanly to redline. No codes the last time I checked, but will check again. Emissions numbers were very clean, although the problem has worsened since the last smog check 9 months ago.
Recently replaced with no change in symptoms: injectors sent out and cleaned, plugs, cap&rotor, wires, 02 in front of cat, cleaned MAF. Compressions are even, across the board. Coolant usage: over 3 years or so, it appears to have lost a smidge.
Any ideas and thanks for help! If necessary, I would be willing to try a socal shop for diagnosis, but thats a 3+ hr drive for me/ea way.
-Jim
