Is this normal or is it a problem. When i'm getting off an exit on the highway and i put my car in neutral the rpm's contuinisly bounce from 700rpm to 1400rpm ? It doesn't necessarily have to be getting off an exit, just when i'm rolling with it in neutral above like 30 mph.

 

I've never experienced that. It doesn't seem normal. when I put my car in neutral at any speed, the rpms just drop....but never bounce back up.

 

Yea its weird, it seems to do it more often when i'm going over 30 mph. Also i have a manual tranny just to make that clear. I have a intake, a header, a s-pipe, an a exhaust too. I don't know.

 

No check engine light currently with the header/exhaust?

 

Nope, i did the nonfouler mod for that.

 

Could be a bad throtle position sensor, or MAF, these things happen. Or perhaps a vaccum leak, somewhere.

 

I was thinking these things also but wouldn't it surge like it is all the time?

 

MINE DOES THE SAME THING... it drops then goes back up to the same 1500 rpms.. but depends on how fast ur still rollin..i think its normal...

 

my car does the exact thing but i also have a lightwight flywheel which is prob causing mine...does your's also do it worse when its cold?

 

wellll all cars do that when its cold since the rpms havent drop under 1k rpms yet...so thats why when u put it in neutral it drops where it was since it was cold over 1k rpms..

 

It's hard to tell if it does it more in the cold.

 

yea but like i said mine does the same thing even when its not cold...when i drop it in neutral it drops, then goes up..but i think never passes 2k rpms even when im rollin 40-50..

 

mine has been doin this for about 1 year now.. and i am all stock engine wise.. so i gess its normal.. nothing else changed.... cept the rattles but thats a whole other issue..lol

 

Mine does the same thing. It is totally stock and has done it from day one and still does it after 34,000 miles. It will eventually settle at idle around 700rpm. But it firsts drops to about the 1500 and then bounces for a while then eventually settles to idle after about 15sec.

 

True, mine i don't think has ever reved past 1500 rpm's

 

So i guess thats just how these engines act then.

 

correct so dont worry..

 

Cool, Thanks everybody for responding so quickly.

 

I've been meaning to post this for a while cause mine does the same thing. Glad to hear I'm not the only one!!!

 

IAC valve..