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Chrysler Repair/my 99 chrysler 300m idle RPM


the idle RPM of engine is around 700, but it's not constant even after reach operation temperature, causing some vibration only in idle when going up or down, i replaced the fuel pump recently and check its pressure, it's 44 PSI and stable do you think it's the EGR valve or any other thing?
another question please, almost times i stop the car and let the gear engaged on D position the RPM goes down slowly until reach 450 and be stable on this value, but some times it still fixed on 700 with some engine vibration, is this normal or i have a problem?
Thank you,,"

ANSWER: Hi Essam,
Try using the ignition key to get any fault codes. Turn it:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window of the speedometer to see if the mileage is replaced by any 4-digit numbers preceded by a P. Let me know if any show up and we'll see if this is related to the idle control issue.

---------- FOLLOW-UP ----------

i forgot to tell you that i did this check before contacting you, I found only the code No.1684 which is not a matter as you know it means recent battery isolation, no more fault codes are available.
Thank you DEAR,,,

Hi Essam,
I would be inclined to open up the throttle body air intake and clean the throat of it, both sides of the butterfly valve, and also clean the idle air passageway on the side of the throat, using carburetor cleaner or similar thin solvent. Absent a code this would be the place to start.
Thanks for the rating/nomination. If you would like you are entitled to do it again, with each successvie q and a.

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Roland Finston


Get a Free Fast answer to your repair question about a Chrysler/Dodge/Plymouth car, minivan, SUV, or truck. Problems with electronically controlled engines and transmissions as well as body wiring problems are my specialty. This free troubleshoot advice forum helps you diagnose faults, minimize repair costs or do-it-yourself.

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