bigTALLguy

Hey guys, i was looking at some of the older forums about what all of your cars idle at and mine was right with most of yours, about 750-800 after warming up. but then, the other night, i went out to my car and the battery was dead (the lovely shaker amps drained my battery). so i put in a new battery with 590 CCA, which is also the same rating as what my car had before. but now the idle is at about 450-500 after warming up. does anyone know whats going on or have any suggestions? i'd also prefer to stay away from the super expensive ford dealers if possible. thanks in advance.

hammeron

you could start by:

cleaning the MAF
cleaning the throttle body

it could also be charging system and/or
PCM related....



good luck and let us know what the fix
turns out to be

ski

Did you try the following procedure from the owner's manual when either replacing the battery, or disconnecting its cables?

1. With the vehicle at a complete stop, set the parking brake.

2. Put the gearshift in P (Park) (automatic transmission) or the neutralposition (manual transmission), turn off all accessories, and start the engine.

3. Run the engine until it reaches normal operating temperature.

4. Allow the engine to idle for at least one minute.

5. Turn the A/C on, and allow the engine to idle for at least one minute.

6. Drive the vehicle to complete the relearning process.

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bigTALLguy

ok, so i did what ski said, sure enough it worked. i think the cars programming had to just get used to everything again, that's all. thanks guys!

ski

You're welcome. Glad to hear you fixed it.

Nuke

Cool. I was thinking maybe a tune needed to be reloaded. Great input, ski.

ski

Thanks, Nuke. I've found that procedureseems to"git 'er done"whenever the battery is replaced, a battery cable is disconnected, or a tune is reloaded.

157dB

The adaptive learning needs to be relearned.

rayfromtexas

2007 GT manual. Saturday went up to car wash, washed car, came home. All was fine. Opened hood to check things, found corrosion on black battery post. Disconnected, cleaned reconnected. Forgot to restart car. Monday driving to work low rpm / car stalled every stop. Had to 'fearher' throttle to keep running. At lunch came out, disconnected battety, reconnected, started and let it idle. Seemed ok. After work started fine but then low rpm / stalled on way home (15 min drive, 5+ miles). So again, disconnected, reconnected battery. This time let it idle for literally 5 or more minutes; rpm was about 750. Tried driving around neighborhood and again low rpm / stalls when clutch/brake for stops. Had to feather throttle. When I parked, it stayed about 500-750 rpm. I'm just wary of trying to drive it now. It stalled in a turn and no power steering. Thankful nobody near me. Any ideas?

HypromanGT

Did you do the procedure outlined by Ski?
FYI every time you disconnect/reconnect the battery you are basically starting over.
FWIW, I don't remember ever having this issue with mine (08 GT). However, I have a 2014 Subaru WRX that does this if I disconnect the battery. It's super annoying, but if you do the procedure outlined by Ski and/or drive it around for several miles it eventually figures itself out.
Thank all the technology, I guess.
Weird that it idles normally, but...I also seem to recall that there is a different directive for "neutral idle rpm" and "drive rpm". There is definitely a difference between A/C on and off, which is why his procedure includes turning the A/C on.