idle air control

[garunner]

I've got a 96 ga se 2.4 twin cam. I've replaced almost every sensor, plugs, mod., coils, housing, fuel filter, air filter and it still runs like garbage. The iac is the only sensor i have not replaced. My questions are: Does the iac move inside? , Can the iac cause a misfire like problem? Sometimes the car will run normal with a hesitation, and at higher speeds it runs like it has a misfire and out of the clear blue "click" it runs normal. I don't understand it. Also the gas milage sucks something bad. I went from 320 miles per tank to 145????? wtf is up with that? So if anyone can answer these questions and give me any kind of input on the iac i would be very happy. thank you

[Brad97GS]

The IAC valve should only have an effect on the car when the throttle is closed, so I doubt that's your problem. Maybe the problem lies in the ECM? Has the car been run on a diagnostic machine?

[Jason Lesbirel]

There is definitely something wrong with the 'puter, if you've replaced the oxygen sensors, along with everything else. Usually the mileage will take a dive like that because the ECM is running in a "limp home" mode, forcing the engine to run rich. A friend of mine had a similar problem with his Civic, albeit for different reasons (box in limp mode, but because of missing sensors - he had performed an engine swap that didn't go well).

You should defintitely get it to a diagnostic centre soon.

[garunner]

I just replaced the iac and the car idled normal. The plugs were carbon fouled so i replaced them also and now the car is running good.I just have to reset the computer to complete the job. I have already replaced the computer so i hoping this is it, and i can spend more time fixing the rest of this thing up.

[Toyguyz]

Your post makes me wonder if it was the carbon fouled plugs that caused the miss? Perhaps they got fouled as a result of a previous problem that got corrected when you changed out one of the sensors but not before fouling the plugs causing a continued miss issue... :???:

[garunner]

The car was missing before i changed the plugs, they were carbon fouled when i pulled them out. I've changed a couple of sensors after that,like the map,air temp, temp sensor. And now the iac, the car idled real good, but would rev with a slight miss, so we changed the plugs again and so far it's running normal, but like i said i have to reset the ecm to put everything back to normal.