so yesterday after work around 5:30PM in sacramento close to about 100 degrees, i noticed my RPM needle was at 2k in neutral. I had ac and stuff running, even after driving for 10 mins i noticed RPM needle would not come down from 2k.

Even when i shifted and pop the clutch it would not come down from 2k.

so I unplugged the battery for few mins and everything reset back to 1k, everything was normal.

This morning everything was fine drove to work about 10 miles needle at 1k or close to it. everything normal


today around 4:00PM about 100+ degree weather RPM needle would not come down from 2k and stuck at 2k again.

Any ideas? could this be due to hot weather? my G is out of warranty so cant take it to the dealer.

thx

 

I don't recall my 6MT doing that after it's been warmed up, but as a quick test the next time it does this, try turning off the AC far a minute or so to see if the ECU is deliberately revving the motor to power the increased engine load caused by the AC compressor and the alternator to run the electric fans at high speed. If the idle backs down, then I'd say it's doing its job. In general though, make sure your cooling system is in good shape.



EDIT: I just noticed you have a first gen vehicle. You posted this in the 2nd gen section, so you may want to ask over there to see if it is something more common/familiar to them.

RE-EDIT: I just reread the thread title, so I guess you are in the right place, you just need to update your sig.

 

^ lol

@OP: its normal for the car to idle at 2k for a couple of mins for the first start after being parked for a few hours (enough so that the engine is completely cooled down) regardless of outside temps and then idle should come down to its normal and next time you start while engine is still warm/hot it should start and idle at the regular ~700rpm...

is this what you're experiencing or is it revving high on engine start even when the engine is hot/warm?

Try looking up the idle relearn.reset procedure on this site and try that first

 

^^ I assumed he was referring to when the car was already warmed up, but apparently my reading comprehension has been severely lacking so far in this thread, so who knows.

 

When the car is warmed up does not go down from 2k


As a matter of fact when I turn the car off after 30 mins of driving needle is stuck at 2k rpm.


Only if I reset the ecu will it back to normal. Until I drive in hot temps

 

OK, that's actually something entirely different. I think that's a heat related issue that affects the tachometer in the gauge cliuster. If you look at recent threads/posts here, there have been at least two in the past week due to the recent heat wave. I'll see if I can't find a link for it.

 

I recently purchased the car, but have heard about ac compressor going out, I will be replacing the cabin filter soon since there is a strange odor maybe filthy.

It's weird in hot temps needle is at 2k rpm but car acts as idling at 1k rpm

 

Here, I got a link. Read this thread (https://g35driver.com/forums/g35-sed...007-sedan.html) and the link included in it to another thread about heat related tach issues.