2004 Ford Ranger Low Idle

http://www.therangerstation.com/tech_library/camshaft_position_sensor.shtml

is the check engine light on is so have code read 1st-second try cleaning the throttle body where air goes into the engine where the rubber hose attaches clean with a throttle cleaner wipe cleaner out i say this due to the idle air control motor may be dirty,and last you may have a faulty egr valve

88 ford ranger 2.9 surges buck down when take off in first gear

does car have engine codes? sounds like your idle air controle valve is sticking. or possible egr problem

Please check your idle controller whch is normally located near the air intake.Sometimes cleaning them and putting them back solve this problem.

Inspect / replace the idle sensor.
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Take your vehicle to AutoZone for a free "check engine light' analysis and ask for an explanation print-out. Have them reset the PCM (check engine light).
Let us know the code and summary of the print-out.

Assuming fuel delivery is OK the drifting idle speed could be a vacuum leak. Check all vacuum hoses and along intake gasket for leak. Also check for leak around possibly worn throttle shaft and around egr. Be sure to also check the curb idle speed and setting for idle kicker if equipped with a/c.

Hello:;
This sounds like a fuel problem at the carb. What it's doing is termened hunting a nd can generally be corrected by a simple adjustment of the carb. Engine at idle and neutral set rpms at lowest idle , around 640 rpms. then adjust the a/f ratio screws to balance carb. Screw both screws all the way in, do not force ,or needle and sear damage will occir. Now back each out to 1.5 turns That is your start point Adjust one screw in and out slowly until you you feel its best effact on ide whicjh should slightly increase. repeat with other screw, in and out slowly . listening to the engine idle. if idle has increase due to your adjustmebt, repwat process after lowering the idle speed again with the idle screw. When you get to the point the screws no longer affect the idle the engine show sound and run smoothly at idle, make sure you resert the idle to 650rpms for an automatic trans and 650-750 for manual trans. I hoped this helped- good luck.. If it still does it, the carb may nrrd the float checked and st.

vacuum leak someplace for the low idle problem,Fuel filter clogged, bad fuel, spark plugs need changing,for the cranking problem.