Engine RPM dropping below normal idle??
 

My cars RPM has been dropping below normal idle when I shift into park or from reverse into drive. Sometimes drops as low as 300-400 rpm and then back up to normal. Anyone know what might be wrong? Thanks

dat fuel saving

Are we supposed to guess what car your drive?

Berz out.

Given the user name I have to ask, does this only happen when you are running into shit?

Have you hit and run recently? PogChamp

Same thing happens with my car, although it doesn't drop THAT low. I cleaned the TB and it helped a lot, could be caused by so many different things though.

Oops 03 jeep liberty

Could possibly be heat soak? My car was doing it back in April/May when it was really hot

With little data to go on, when was the last time you did any maintenance it and what was done?

The cause could be a variety of things...

I always do the basic fluid changes but havent touched tranny fluid for about 70k now. It has about 150k on it and I daily this car but for the past 2 months it was parked and I noticed this happening after i started driving it again 2 weeks ago. Would anyone recommend trying Seafoam ?

Does your car ever stall out while it's idling from dropping rpms so low?

Last winter, my Mazda3 had an issue where it sometimes would stall itself out while idling.
Turned out I had to replace the Purge Solenoid Valve

I have full I/H/E with no tune, I've read and been told that it could potentially be non-ideal AF. Could be timing as well, or TB, or trans fluid, or a whole other list of things. Although I know for certain back when the car was devoid of any modifications, it never did this, which leads me to believe it's probably AF, in my situation at least.

If it makes a difference, my car has stalled before shifting from P to R and R to D :lawl: not even a manual.

Try cleaning the TB, if your car is anything over 100k, chances are your TB is quite dirty. TB cleaner is cheap, buy a can and clean it, it doesn't hurt anyway.

Sorry thread jack, there are headers for Honda Element? Cool!

no it hasn't stalled yet just dips down and then goes back up. Gonna try cleaning the throttle body, anyone recommend a good brand?

Try cleaning your Idle Air Control Valve along with your TB.

If it consistently dips to a lower level it might be emissions related.

^+1 on the IACV

Does it ever drop when its cold?

Any K swap long tube works :derp:

Also, IACV didn't work for me. I changed it at around 310,000kms and it didn't help at all, but cleaning the TB made a huge difference.

No it hasnt happened yet while the cars still cold. And I also noticed it only started happening once the weather got warmer recently.

If you're going to clean the TB, wouldn't hurt to do an idle air relearn