yoss626

Adjusting The Idle

13 posts in this topic

Is it possible to adjust the idle on a 1998 626 4 cyl?

if yes, how? can you adjust with a screwdriver somewhere, or is it controlled by the computer with a idle control valve? (If there is a idle control valve, where is it - I could not see one on my car)

Thanks alot folks

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Your engine is computer controlled. You should never ever have to touch the idle stops.

The IAC is bolted to the throttle body.

agreed , it can trough every thing out of whack and make diagnosis more difficult. what kind of idling problems are you having?

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Your engine is computer controlled. You should never ever have to touch the idle stops.

The IAC is bolted to the throttle body.

agreed , it can trough every thing out of whack and make diagnosis more difficult. what kind of idling problems are you having?

the car always idled at like 650 rpm. it got great mileage.

the other day I cleaned the throttle body with a small spray of tb cleaner .

ever since then it's idling around 1100 and this local(city) mpg's have dropped.

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Make sure the butterfly in the TB isn't sticking and that the throttle linkage moves freely. Make sure you hooked up any vacuum lines or electrical connectors you might have disconnected. A vacuum leak will cause your high idle.

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you could have also dislodged some build up that's stopping the throttle from closing.

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Your engine is computer controlled. You should never ever have to touch the idle stops.

The IAC is bolted to the throttle body.

agreed , it can trough every thing out of whack and make diagnosis more difficult. what kind of idling problems are you having?

the car always idled at like 650 rpm. it got great mileage.

the other day I cleaned the throttle body with a small spray of tb cleaner .

ever since then it's idling around 1100 and this local(city) mpg's have dropped.

I'm here searching this site because that's exactly what I did two weeks ago (cleaned my throttle body and now have a high idle of 1100 - 1200rpm). I can pull it down to 700rpm if I let out the cluthc and apply some load to the motor while the brake is on. It will kick back up to 1100 as soon as the fans cut in though.

I have completely removed the throttle body and cleaned every aspect of it to make sure all the juke was out and I still have a high idle. Have no idea what has caused this.

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rooboy-try putting it in diagnostic mode and adjust the idle air screw. look for vacuum leaks as well.

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Do you mean link TEN and GND, start the car and then adjust the idle screw? I've played with the idle screw before but not in diagnostic mode. What's the significance of this?

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it stops the computer from interfering or confiscating while you adjust it.

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When I pulled the TB and cleaned it the idle afterwards was at 2000 rpm's for a couple of days. It then came back to normal a couple of days later. I'm suspect that perhaps one of the sensors that was still attached when I cleaned it had cleaner puddled and was causing the idle to be up. Alls well now.... Good Luck! ;)

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The only way I could get rid of my problem was to replace the BAC and IAC valves (grabbed a second hand throttle assembly from a wrecker) which lie under the throttle body. I replaced both oxy sensors the week before (after 255K they were dead, according to the computer). It made no difference to the idle issue however on the up side I'm now getting an extra 70Km out of a tank!

I'm not sure why this was the remedy to my issue when all I did was clean the thing out. Maybe the carb cleaner had some effect on one of the valves. I hear they can be pretty harsh on plastic components sometimes.

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some of the iac internals have a wax coating the carb cleaner brings off. use maf cleaner.

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