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2005 GT P0506 RPM Low after battery issues

2156 Views 1 Reply 2 Participants Last post by  ski
I realize this issue has been addressed before, but I feel like my situation is different enough to start a new thread.

So my temp gauge has always been loopy (pointing straight down, ect.), but recently my car had an issue starting. It's like the battery was dead but then it just jumped back to life. My CD Player was reset and everything. Then a day or two later it just wouldnt start, and all it took to get it goin was a rustlin of the battery cables. Turns out they were pretty loose. So day or two later I realized the Check Engine Light was on. So I got the code diagnosed at Jiffy Lube, and it said "P0506 Idle Control System RPM Low". I havent noticed any sputtering or jolting or stalling or anything like that. and the idle RPM never dips below 600.. I didnt have the code cleared or whatever, prolly do that tomorrow... I have no mods, no upgrades (I know, lame), so what do ya'll think?

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The engine should normally idle at approx. 750 rpm, and the dips down to 600 rpm may be low enough to trigger a CEL.
The loose battery cables probably wiped out the ECU's idle strategy, and now it has to re-learn the idle, which is causing it to dip to 600 rpm. Driving 20-50 miles should be sufficient to allow the ECU to re-learn the idle, and stabilize it at 750 rpm.
There's also a procedure in the battery maintenance section of the owner's manual that may expedite the idle re-learning process.
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