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i have taken the golden "cap" off my IACV to make it like hte newer ones because i was scared that a screw might go into the engine. i have cleaned it too. now the prob, the car idles at 500-550 when in a gear. in park it is about 700. since i took hte cap off to make it like hte newer ones, i think the idle screw is adjusted differently then mine. should/do i need to turn the black plastic screw to adjust my idle? if so in which direction do i turn it. or do i need to clean my intake air filter?
How do I clean the IAC valve...what exactly is it, I know to follow the large hose to the throttle body and is near the purple /pink connector...now which one is it and how do I clean it...need pics to clear up the confusion??????..help need to do this ASAP
Just take it out (3 screws) and on the inside there is a metal cap that you unscrew. I cleaned the whole IACV inside, the cap that was removed inside, and the area under the cap. Use carb or throttle body cleaner.
well after i cleaned the IACV the first time, i tightened the screws really tight. and then i asked hte question about the screws and i was told i can take it off. i did take it off and when i was unscrewing the 3 screws, they were very easy to take off.
so, can/should i adjust hte black plastic screw on the IACV
I think your 700rpm in park falls under normal range. However, if you are concerned your base idle may be off, the proper way to confirm and adjust that is adjusting the black IACV set screw with the TPS (throttle position sensor) disconnected.
(1) With car off, disconnect TPS. Make sure you previously have driven the car and it is normal operating temperature. Make sure your A/C-heater is off.
(2) Start the car and rev it a few times... then let the rpms drift to base idle. If need be, increase/decrease the base idle rpm to normal range via the IACV set screw (black plastic). If the limits of the set screw have been reached but the idle rpm is still out of spec, you will have to adjust the throttle plate screw to get it in range, and then fine tune with the IACV screw.
(3) Reconnect the TPS and start the car.
When in gears, you are then NOT looking at "idle." The procedure is only for park/neutral. My car only has one TPS connector but if yours has two, then by all means disconnect them both. When the TPS is connected, your ECU is always trying to correct the rpm so you should not adjust the IACV under that circumstance.
ok people, i just did hte "base idle" and it was at 400, i turned about 1 and a half turn counter clockwise and it went up to 750. i turned off car and connect hte tps. i turned back on it was a smooth turn on, i turn on a/c, rpms all good. i turn off ac and then put into reverse. the rpms drop to 550 but it doesn;t vibrate the steering wheel like it did eariler. i put in neutral and it goes back up to 700. i put into d and drops back down to 550 and no vibration. remember the car is not moving, i have my foot on the brake and when i let go, the rpms still are at 550. should i be concerned at al about hte rpms dropping to 550 in the gear or not since it doesn;t vibrate? also the rpms are at 650 when hte ac is on while i am in a gear.
thnx for your help
In gear rpms is affected by a lot of things: load, speed, gear...etc. As long as it doesn't shake like it's choking or about to stall, I wouldn't worry about it. Then again, I don't have an automatic so can't really say for sure...