99 Corolla misfires
jpg366
06-11-2006, 07:49 PM
Recent problem .... solved... nope, not solved. see below.
Symptoms ... hesitation and stumble off the line, or when increasing throttle slightly. Idle OK, mileage OK.
Codes indicated random misfires, particularly cyls 2 and 3. Those share a coil, so I measured secondary resistance of both - OK. Went ahead and cleaned low voltage connections on both coils.
Pulled plugs - all looked the same, no carbon, OK. Must be a fuel problem.
Cleaned and reattached electrical connections to all injectors. Sprayed some carb cleaner into the throttle area. Put a bottle of Lucas fuel additive in the tank.
Now misses are gone, and all seems to be well. Apparently 6 or so years lets low voltage connections accumulate some unwanted resistance.
Symptoms ... hesitation and stumble off the line, or when increasing throttle slightly. Idle OK, mileage OK.
Codes indicated random misfires, particularly cyls 2 and 3. Those share a coil, so I measured secondary resistance of both - OK. Went ahead and cleaned low voltage connections on both coils.
Pulled plugs - all looked the same, no carbon, OK. Must be a fuel problem.
Cleaned and reattached electrical connections to all injectors. Sprayed some carb cleaner into the throttle area. Put a bottle of Lucas fuel additive in the tank.
Now misses are gone, and all seems to be well. Apparently 6 or so years lets low voltage connections accumulate some unwanted resistance.
jpg366
06-16-2006, 08:54 PM
Update ... problem is back. On acceleration, acts like it is not getting more fuel for a second or two, then takes off OK. Continuing with Lucas fuel treatments.
Any thoughts about what might allow it to bog for a few seconds?
Any thoughts about what might allow it to bog for a few seconds?
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