1992 240sx Low idle

[mwa3c]

New to the forum!

Just picked up a 1992 240sx. the car is a champ! runs smooth as glass EXCEPT the idle is a bit off. it sits about 500rpms. Where do i start?

I was thinking that the Idle Air control valve may be carboned a bit. debating on removing it and cleaning it. BUT before i do.. do you have any sugestions?

Resaon i am thinking idle air controle valve is because when i hit the a/c the idle will jump up to about 900rpms until i turn the ac off..

The car has NEW plugs, wires, distributer cap + rotor. (idle condition existed prior to new parts) car has 127,000 miles on it..

Has slight valve cover seapage..Pulls as hard as you would think a 2.4l would.

Has anyone run into this before?Thanks~ Mark

[MoldyOldy240]

Welcome to NICO. You may want to search for the problem you are having, but heres a suggestion.

Try changing the idle on the ecu, it is located on you passenger right side kick panel. You will have to unbolt the two bolts holding it in to see the knob you will need to adjust.

The previous owner may have used the ecu to diagnose a problem, and forgot to set the idle correctly.

This is just a shot in the dark, but hey, it could work.

[vancouverbc]

your idle is supposed to go higher when you turn your air conditioning on.the fast idle control device(ficid) is part of the iacv.

you increase idle by turning idle adjustment screw counter clockwise. the screw is on the iacv. you access it under the hood on passenger side at the back near firewall.

This has nothing to do with the ecu inside the car as the previous post suggested.

If you want to adjust idle with car running you have to disconnect the tps as the following indicates:

Adjusting the idle is pretty straight forward:

Disconnect the TPS harness and turn the idle adj. screw on the IAcv to get the car to idle at 650 rpm. Reconnect the TPS harness and your beloved should purr at 700 or so rpm. (The Factory manual gives a +/- tolerance of 50 rpm.) The IAA is at the back of the intake manifold. You can see it standing over the right (passenger side for N.A.) fender and looking at the funky device with the dime size recess for the adj. screw.

[mwa3c]

i tried to play with the computer on the car but ended up just throwing check engine lites.. i found another article talking about how to adjust the aic (idle air control) valve.. did that and VAROOOM all better!

Thanks!Mark

[onecrazyfoo4u]

Do you have a link to that thread? I"m having some idle problems just like you are. Thanks!

[vancouverbc]

Do you have a link to that thread? I"m having some idle problems just like you are. Thanks!

The op only had a low idle. he just manually adjusted it. this might have been the artilce. it tells you how to adjust idle at the bottom.

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