Hello, I have had my evo x for about two weeks now and I love it, there is just over 35k on it and it was well maintaned by the previous owner. It is stock and has never been modified and I have recenlty noticed that under full throttle acceleration its almost as if after it spools the boost drops in and out on a minor level, like someone took away ~25 horsepower for 500 rpm then gave it back for 500 rpm or so and then took it away again? its not rough or shakey at all just feels like once its pulling the power falls off and them comes back and then falls off between 4-7k
Any ideas?
Thanks guys and gals

 

If its never been modified this is most likely due to the crappy stock tune the car comes with. You will feel a world of difference with a reflash.

 

Yea the guy who bought it new was much older and didnt mod it outside of a K&N drop in replacement.

But I was thinking it might be the stock tune,
** I noticed there is a TSB sticker on the underside of the hood and I took it into Mitsubish to find out what it was, if it was a recall item or something and it turns out it was a reflash from the factory so that might have something to do with it???

TSB SC-009-002 < --- JUST found this 09-002 in the list of TSBs on the general x forum AWC ECU reprograming
PN 8631A040

Already order an Accessport
cant wait!!

 

Heeh, that's normal! You pretty much summarized the stock tune of the Evo X.

 

Happened with my 08...I posted a few times and it always was crappy mitsu tune.

 

It's amazing what an OTS map can do for power and drivability. Enjoy.

 

Mine does the same thing, I bought the ETS Intake/IC hoping that would rectify the problem on it's own.. no. There is no substitute for a good tune, so I have a tactrix 2.0 on its way to me now. After payday Ill order the boost gauge and wideband, then its play time.

 

Awesome, that was the feedback I was hoping to get, all hail Mitsubishis poor tune....
Makes you wonder why its tuned so poorly from the factory? Probably has to do with Americas strict laws governing foriegn vehicle performance...
as far as i know the FQ 330 / 360 for the most part benifit primarily from better tune where as the 400 has more upgraded components.

 

Correct.

Im fairly certain it has everything to do with emissions and performance regulations. or they were just scared to tune the car lean, and went with the safe... super fat.

 

my o8 did this also. You just need a tune

 

is it still on the original clutch. kinda sounds like your clutch is going out.

I spoke to a local tuner over the weekend. He says the reason the clutch going out doesn't feel like a typical slipping clutch on our cars is cause of something called torque request or something like that... basically what happens is the ecu monitors the wheel speed and the flywheel speed. if they don't correspond correctly the ecu will pull power to try and save your clutch. so when you drive it, it feels like a bad tune...

not saying this is exaclty whats happening in your case, but its prolly worth looking into

 

That would make sense as well, might have to look into that,
when I get the accessport in this should be evident if that is the case, which means ... new clutch

 

Go to the dealer there is a recall and they will reflash your ECU. Had the same thing above 5k the power dropped. This was an issue with the factory tune. After the dealer reflashed it's like a different car.

 

Sorry, but I do not agree. When the clutch slips in the X, it slips and is very noticeable. The OP issue is the stock tune; it's none linear and very choppy in the upper RPM band.

 

i've had my '09 GSR (entirely stock) for a month now and last night i managed to do 0-60 (actually even better, 0-100km/h) in 4.7 seconds! didn't use any sophisticated equipment and didn't have a passenger. i just set the countdown alarm on my mobile phone and as soon as i let go of the clutch i simultaneously started the timer and dropped the mobile on the passenger seat. i had hit 100km/h exactly at the 4.7sec mark, which was my goal. i'll try to do 4.6 next time