My beloved lil' GA16DE motor has developed this strange idle. At times when I come to a stop I feel the car pushing along. When this happens, I put the car in neutral and find the revs rise to 1500 and even 2000 RPM sometimes. To fix it, I kick the accelerator and after a jump in rpms, the idle immediately settles back to about 800 rpm. I tried cleaning my throttle body. Is it the idle air control valve I need to clean?
Thanks
That sounds a lot like what I've been trying to figure out in my '99 Altima. PLEASE if you figure out what the problem is, let me know! The dealer has been over mine a few times and not found anything, but I'm convinced there is a problem somewhere. Mine more or less disappears after the car warms up completely, but in the winter it doesn't always get to that point.
I have also cleaned my throttle body, plate, and IACV, and ended up replacing the IACV due to a seized idle screw, and still no change in the problem.
"JM" quipped:
both of you sound like you both have a classic case of a bad idle air control valve as Codifus suspects.
Forgot to mention that I have replaced mine, with no change. It seems as if the ECU is holding the valve open unnecessarily. Mine will also rev up as I am easing into the throttle, with the car stopped in neutral. After crossing about 1000 rpm as slowly as I can, it suddenly takes off up to around 1500-2000 rpm.
Is replacing the IACV the only option, or can I clean it?
CD
My problem occurs only when warmed up, or maybe it's not so apperent when cold since the idle is higher anyway.
Goosing the throttle always makes the idle return to normal.
i'll give the IACV a thorough cleaning and see what happens.
Concerning your Altima, venturing a guess, since your problem only happens when cold, and from the way you describe your issue, I would think that it is something electronic, not mechanical, perhaps an RPM or emissions sensor of some sort.
CD
Should be able to clean it and reinstall, I tried that on my Altima but no luck. ISTR hearing the Sentras have them in an accessible location, mine is buried under the intake manifold and took me a good 45 mins to get out. Be careful with the gasket though, if it leaks when you put it back it'll probably throw the idle off more.
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