its not the gas cap Bommie!! it was bouncing between 200 and 1000 today. nuts.

I'm taking it to another dealer

after that, i'll see what i can do to beat ya

 

Mine's goes to 500rpm too. Thats in between the first and second mark.

I don't know about 200rpm though. I'm going to get a tactrix cable soon to log this stuff accurately.

 

get a baseball bat?

 

now seems like this occurs every couple weeks.
bounces about 20 times each time it happens. sounds like the car is chocking or something.
I found when it happens either if I rev up or turn on the AC, the bouncing stops.

anyone else with the same problem?

 

do you still have your factory intake? If so, make sure it's closed properly.

 

Sounds like a vacuum line problem. Supposedly there's a line that runs from the fuel pressure regulator to the intake manifold that can pop off under pressure. Whether the RA has enough boost to pop that line off is still debatable, but it's worth taking a look. Another poster had similar issues on his X the other day and had a nice write up about the fix. Here's the link: https://www.evolutionm.net/forums/ev...s-do-asap.html

Hope you find the fix.

 

Hi Everyone,

I'm from the Evo X forums, and it seems that this rev dropping issue is also common among the Evo X's as well. Between the regular Evo X owners, I think we've agreed on two solutions for this issue:

1. Get the latest dealer ECU reflash- although there are some people that still see this problem occasionally, even after the reflash
2. Make sure the rubber hose of the fuel pressure regulator is connected. This hose falls off frequently, and if it's disconnected, you may need to ziptie that sucker. It's right next to the engine oil dip stick.

Please see this thread:
https://www.evolutionm.net/forums/ev...y-dipping.html


Hope this helps.

 

Still bounces hard several occasions in few months even after ecu reflash/sw upgrade/vacuum hose replacement/tachometer adjustment. Gave up on this issue. All these dealer stuff did make the bouncing occur a lot less times tho. Thanks.

 

2009 ralliart 80,000 miles stock, eversince I got the car brand new, once in awhile I would get this bouncy idle at a stop light, almost feels like the car will die, and the car shakes, at first I would place it in neural and rev a bit till it goes away, but now when it happens I just let the car work itself out, it has never died so far and runs fine after, I just tell myself that the computer might be acting up. I've tried to post this problem before but no one seems to understand what I mean till now.

 

I have the same issue, it usually happens right after i hit boost and have to come to a stop quickly

 

I'm in Maryland as well. Where are you located? What dealer did you take it to get looked at?