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Re: Andres-- Is it AIC problem or auto box? Posted by SWEDECAR [Email] (#112) [Profile/Gallery] (more from SWEDECAR) on Mon, 13 Sep 2004 10:25:59 In Reply to: Andres-- Is it AIC problem or auto box?, Harry, Sun, 12 Sep 2004 19:40:07 Members do not see ads below this line. - Help Keep This Site Online - Signup |
The ECU of the car is suppose to raise the idle when drive is engaged to compensate for the extra load that the transmission creates.
The amount of raised idle though should be a wash to what the transmission creates in drag, so you should not really see an increase on the tachometer.
It's difficult to say if the ECU for some or another reason raise the idle more than it should or if the transmission for some reason creates less drag than it should.
I would probably suspect the first more than latter.
It could be a ground wire problem somewhere that allow this to happen, the problem could be to find it though and a lot of measuring each wire would be needed.
Even a corrupt ECU could do this.
I would start with finding all visible ground connections around the engine compartment and battery connections and remove/clean everything.
The ECU also compensate the idle when A/C is turned on so that it maintains a stable idle when A/C compressor is cycling on/off.
Is the A/C working properly or has it been disconnected? If A/C compressor is disconnected (electric wire) at the wrong place, the idle up compensation is still taking place even though the load from compressor is gone.
Anders
posted by 67.113.87...
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