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91 2.3 idle problem manual trans

1184 Views 10 Replies 4 Participants Last post by  Michamike
Just adding this info in because it may help solve my problem. A month or so ago I posted how my check engine light comes on and my rpm gauge jumps all over the plays. Even though the gauge jumps, it does not effect the true idle of the car. Now my car starts up fine goes to idle around 800 to 1000 then drops to 500 or lower. At that point it ether stays idling around 500 or just dies. Car will start right back up after it dies. If i feather the pedal and keep the rpms around 800 for 5 minutes and let go off the gas the car will idle fine or if I drive it for a few minutes it does the same thing. The only changes i have done to this car lately is that the day before the idle problem start witch was this last Friday. Is that I disconnected my negative cable to hook up a new socket for the light under the hood. I also put on a new clutch cable. I did a full tune up about a year ago and I have only put 5000 miles on it scenes then. I am bout to just take it down to the Ford dealer and have them run an engine diagnostic if i can't get this fixed over Thanksgiving week end.

Thank you for any help
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search either the site itself, or search my threads for how to pull codes. its easy to do yourself and it will save you a c-note at the ford dealer. even if you buy your own code reader you will save yourself money, theyre only $25-30 at the parts stores.

since you dont have codes yet, its more guesswork, but the likely suspects would be the maf, idle air control, or possibly icm.

however you get the codes, post em up when you get them. but also let us know what parts you replaced as part of the tuneup.
i could be wrong, but doesnt 91 have a mass airflow sensor? a bad maf will just screw up everything. i'm also adding to my previous guesses-the throttle position sensor might have a bad spot in it.
since youre getting a code reader, obviously post codes when you have them. it always helps when someone pulls codes beacuse it cuts down on the ammount of troubleshooting work we have to have them do to find the problem. once we have codes we can pretty well tell you what you need to replace and why, since the computer has done all the component testing for you :winks. i love being able to pull codes rather than having to spend an extra hour in my unheated garage screwing with a volt meter to bench test half a dozen parts when something starts behaving badly in my stang.
and no worries on a late reply, we all understand that real life stuff happens and sometimes fixing the mustang must wait.:yup:
the fan is supposed to cycle for a few seconds, its one of the things the computer is checking for the test.
are you positive that all youre getting is a code 10? I am pretty sure 91 should make 3 digit codes. and also theres no number 0 in codes. if you can, post up a vid of every single flash the code reader makes.
you should at least be getting a code 111 (for 3 digit years) or a code 11 (2 digit years). those are the system pass codes and if there are no problems then you will get that code.
the k &n filter could have screwed up or killed your mass airflow sensor. the oil on the k&n filters really wreaks havoc with the fillaments in the sensor. definitely use that maf specific cleaner you bought to clean it with. unscrew the maf from the housing (so you can get to the filament portion of the sensor) and unplug it from the wiring harness when you go to clean it.
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