ok, so recently, my car has been sporadically dropping in rpms. down from 900 at idle, it will plummet down to like 400, then jump back up. its done this only twice over the last 2 weeks.
well TODAY, after some mildly spirited driving, I get in to go to work, and as im coasting in neutral to a stop, my rpms stop at 1500, and when I got under 20mph, they started dropping til they reached 900.
I also noticed, if I shift to 2nd or something, and the rpms drop lower than 1500 after putting the clutch it, it will actual raise to 1500 in neutral.
So I took my throttle body off, cleaned everything with carb cleaner, there isnt a spec of dirt left on the thing, took the idle air control valve, and it opens and closes as it should, granted it does take more force than it looks like it needs to move. the butterfly opens and closes perfectly, I dont hear any vacuum leaks, and I dont have a CEL.
so what gives. Do I need to replace this $80 sensor?
IAC is not a sensor.
Sounds like normal operation for a J body to me. If you are just now getting this issue you are lucky.
Its normal for it to idle 600 rpms more than its supposed to? then drop back to normal after I get below 20mph?
next.
Borderlin3 wrote:Its normal for it to idle 600 rpms more than its supposed to? then drop back to normal after I get below 20mph?
next.
You never mentioned this in your first post.
For a manual car if you are at a higher speed and slowing down it is normal for the RPM's to raise and hold around 1500 RPM's and slower lower as your speed lowers. Usually as you get under 20mph it will hover around 1100 RPM until you come to a complete stop.
FU Tuning
Borderlin3 wrote:
well TODAY, after some mildly spirited driving, I get in to go to work, and as im coasting in neutral to a stop, my rpms stop at 1500, and when I got under 20mph, they started dropping til they reached 900.
yeah I did, and Ive had the car for two years, and its never done this, AT ALL, until yesterday.
I know the car holds its rpms when you are slowing down in gear, but its always dropped down to 900 as soon as Ive pushed the clutch in.
