| Subject: | fuel |
| Question: | 1986 Mitsubishi Starion
ESIR, turbo,5 speed, throttle body injection. What could cause the engine to flood (black smoke,hardly able to idle) when both injectors are connected but great when either one is connected separately? Injectors remanufactured, new fuel pump,filter,air filter, in time, good spark plugs,nothing reported by computer (signal constant) spray pattern of injectors good. |
| Answer: | A failing oxygen sensor will
cause your engine to run very rich. Your computer won't always throw
the code for a bad O2 sensor. You may have a bad idle air control motor,
which can cause a bad idle, and can send false signals to your computer,
which in turn can instruct your injectors to allow too high of a fuel
mixture. Your computer won't throw a code for a bad idle air control
motor either.
Turbo/intake leaks are common causes of poor idle and rich air/fuel
mixtures. Inspect your intercooler, turbo, and intercooler piping for
possible leaking. Remove the hoses and check for cracks and leaks.
Check any of those areas I mentioned if you haven't already. Hopefully
you'll pinpoint your problem. |