My 1990 2.3L automatic with electronic(?) overdrive has just under 240,000 miles. I recently had problems with a spark plug constantly missing, and, I replaced the plugs, wires, and, air filter. Immediately after that, I started having really bad sputtering (not really sure if the problem existed before replacing the plugs). It happens both when the engine is hot or cold, rarely when idling in Park, and, about every 5 seconds otherwise. When it stops the sputtering while driving, it seems to be downshifting. I can eliminate the sputtering by flooring it, and, sometimes I can find a cruising sweetspot - but that only lasts for a few seconds. When idling in Drive, the RPM's go down to close to 500 and occasionally will stall because of the sputtering. When I rev it when in Park, I typically get plumes of black smoke (I do not have white smoke at all). I replaced the fuel filter, but, nothing changed. Even with this sputtering, I am able to get it up to 80MPH and the engine sounds great when not sputtering. Also, the "check engine" light is on, but, I cannot say for sure when it started lighting up (it is kinda behind the steering wheel and not very bright). The only thing I have added to the gas tank recently is something that is supposed to help burn off water in the gas tank. When I stop and get out of the car, I smell a lot of gasoline (and my allegies typically prevent me from smelling almost anything). I left it with a shop that advertises that it works on older cars, but, after 2 weeks they could not figure it out. I have been using 100% gas (ethanol-free) for at least 5 years now. I have used synthetic oil, filter, and, Lucus oil treatment for at least 10 years. My gas mileage has gone from 25 miles/gallon to 10 miles/gallon. I have owned the car for over 20 years and there has never been any work done on the engine.
After that shop couldn't figure it out, I went online looking for any ideas that might be causing it and I came up with this list of possible causes:
- fuel pump
- fuel pressure regulator
- O2 sensor
- TIF module - sputters when engine is hot, but, not when cold
- PIP sensor
- MAF sensor and vacuum hose
- fuel injector cleaner
- coolant sensor
- cooling fan module (E7ZB-8C609-AA)
- vacuum modulator on the transmission
- catalytic converter clogged
- ECU
- ignition coils
- leaks in the intake manifold gasket or vacuum hoses
- Exhaust Gas Recirculation (EGR) valve
- trottle position sensor (TPS)
- engine timing problems
I am no means a mechanic, but, I have worked on my cars for the past 40 years. So, I feel confident in being able to do some of the easier repairs that don't require special tools. Of the things listed above, I don't recall fixing/replacing any of them and I have never had this sputtering problem before. Some of those parts listed above exceed $50, so, I don't really just want to replace each of those parts without knowing that it is a good risk/try. Initially I am most interested in the "cooling fan module" because I don't think that my fan comes on at all (and the fan itself has been replaced). Also, this is my only car at the moment, so, I am not really keen on leaving it with a shop for 2 or more weeks again.
What type of experience have y'all had when encountering this problem? What are some other possible causes/solutions? If I were to take it to a shop, what would be a reasonable amount of time to expect them to be able to fix this problem or give it back to me?
After that shop couldn't figure it out, I went online looking for any ideas that might be causing it and I came up with this list of possible causes:
- fuel pump
- fuel pressure regulator
- O2 sensor
- TIF module - sputters when engine is hot, but, not when cold
- PIP sensor
- MAF sensor and vacuum hose
- fuel injector cleaner
- coolant sensor
- cooling fan module (E7ZB-8C609-AA)
- vacuum modulator on the transmission
- catalytic converter clogged
- ECU
- ignition coils
- leaks in the intake manifold gasket or vacuum hoses
- Exhaust Gas Recirculation (EGR) valve
- trottle position sensor (TPS)
- engine timing problems
I am no means a mechanic, but, I have worked on my cars for the past 40 years. So, I feel confident in being able to do some of the easier repairs that don't require special tools. Of the things listed above, I don't recall fixing/replacing any of them and I have never had this sputtering problem before. Some of those parts listed above exceed $50, so, I don't really just want to replace each of those parts without knowing that it is a good risk/try. Initially I am most interested in the "cooling fan module" because I don't think that my fan comes on at all (and the fan itself has been replaced). Also, this is my only car at the moment, so, I am not really keen on leaving it with a shop for 2 or more weeks again.
What type of experience have y'all had when encountering this problem? What are some other possible causes/solutions? If I were to take it to a shop, what would be a reasonable amount of time to expect them to be able to fix this problem or give it back to me?