I have a 2008 G37s
Whenever i gas it and then when i take my foot off the gas the rpm drops to 500 and then goes back to what its supposed to be at
It happens in first gear,second gear and third gear.
Whenever it happens the car sounds like its about to die but never ever does die
No Mods to car accept a K&N filter but it does it before it had an stock air filter from dealer
Just wanted to see what it could be or see what it might be.
Its just been bugging me for a while and i was worried about it

 

Sounds like vacuum leak, was intakes properly seated and were any vacuum lines loose

 

Double check all of your intake connections and rubber hoses. Make sure they are tight, secure, and in good condition.

A 2008 with unknown mileage- have the throttle bodies ever been cleaned?

 

I think I know, Your torque converter is unlocked, and when you let off the revs have to catch themselves. Chances are it’s not catching early enough, I’d say try it in manual shift mode. Trust me, I hate this transmissions programming.

Make sure the trans is up to temp and give it a shot

 

Everything was plugged in tightly and cleaned the mass airflow sensor and throttle same thing

 

Oh my B my g has 80,700 Miles and they are tight and throttle body was cleaned in june and it still does it so i was just wondering if it had to do anything with something else

 

Ye, i drove it in sport before and it still does it in like first and second at low speed thats where it sucks but it doesnt do often as it is in auto.
Also is there like a fix to this ? A tech said it might be a bulletin update which there is but he said that my car couldnt take the update cuz it was too old he said in terms of the date when the car came out

 

You need to clean the throttle bodies, then do the idle air relearn procedure
https://www.myg37.com/forums/engine-...learn-fix.html

If you still have the issue, start futzing with the trans

 

Well if you ask me, the trans seems to be doing alright. Do what the rest are saying, TB’s, vacuum leaks, relearns and the works.

my personal experience is when the torque converter opens up, the revs drop anywhere down from 600 to 1000 for me. It’s very hit or miss, I don’t honestly know why. I’ve check vacuum leaks, TB’s, done relearns all myself and that just seams to be the way mine behaves.

 

Have you changed diff and trans fluid yet I did mine early before 100k along with plugs rad fluid and other stuff

 

you can get an ECU from a newer model and have it flashed to your car and it should be able to take the update. used ones are very cheap on Ebay.

 

will look towards that thank you very much sir

 

nope but might end up doing that Thank you.

 

Ok will see towards it thank you so much.

 

After cleaning the throttle bodies, did you do the idle air volume learning and the closed throttle position learning?
If not, here is how: