Im curious if for those of you who have had a chance to go wide open throttle on the X... have you been experiencing "Sputtering" issues in high RPM? I going to take it to the dealer to see if they can find anything...

I know that our X's run rich, but I'm unsure if that is the cause that im experiencing...

Sputtering, eh?

How many miles are on your car?

As a start I would look at the fuel. Is it dealer gas (they sometimes put in the wrong stuff)? Wrong octane? Use the highest octane you have available to you. Isn't the Evo X supposed to be 93 octane minimum?

Anyway, WOT at high RPM is fun, but do you want to be doing that to your Evo X when it is so new? This is a good topic to open up for more discussion.

I WOT mine just about everyday but I don't have any sputtering here, but then again mine is the JDM.

I have wot mine but I shift at 6000 rpm because that is the top of the power band.No sputtering from mine.

Sputtering, eh?

How many miles are on your car?


right now it has just shy of 700 miles... I should probably break her in a bit more.. but something just doesnt feel right.

As a start I would look at the fuel. Is it dealer gas (they sometimes put in the wrong stuff)? Wrong octane? Use the highest octane you have available to you. Isn't the Evo X supposed to be 93 octane minimum?

Anyway, WOT at high RPM is fun, but do you want to be doing that to your Evo X when it is so new? This is a good topic to open up for more discussion.

Unfortunately, 91 octane is the highest here in California...

I have no issues with mine on WOT. 4500kms and counting.
Daily WOT as well. (up to redline)..

in addition, around last week, my ASC light started to come on... meaning that the car is shutting ASC off on its own. I am unable to do anything by pressing the ASC button. Once I turn the car off and restart it, everything is fine, but the light will come on again everytime about 10 minutes into the drive.

Definitely gonna get it checked out at the dealer....

in addition, around last week, my ASC light started to come on... meaning that the car is shutting ASC off on its own. I am unable to do anything by pressing the ASC button. Once I turn the car off and restart it, everything is fine, but the light will come on again everytime about 10 minutes into the drive.

Definitely gonna get it checked out at the dealer....
so the recalls are going to start. Dont mod that bad boy or they will void your warranty.

so the recalls are going to start. Dont mod that bad boy or they will void your warranty.


seriously... its only 2 weeks old. So far the only thing different on it is my rims.:shades:

I have noticed some irregular revs with a cold start.... I assumed that it was normal on a cold start..

that does seem i bit strange for it to do that.we need more info on this.

I'd be weary about going WOT so soon in owning my X. Give it a while before redlining.

Yea... I'm gonna wait a full 1k just to be safe. She's gonna be my baby so I'm gonna treat her like a princess. :P

Yeah, im staying under 50% throttle as best I can, until 1500 miles or so. Though, its good to take up the revs during the break in period every now and then. So far though I slipped once, and didn't notice any sputtering. Im running 92 here in Oregon.

Yep. I didn't go WOT till I clicked over 1000kms.
Even though I asked the GM of the dealership if I needed to ease 'her' in.. he said.. 'no.. give it heaps!!'

Yeah, thats a big rat hole. Do you baby it, or drive it like you stole it. I drove my Evo like I stole it, and it turned out to run about 10 to 15 WHP lower then other cars with the same mods. This time I will do the opposite and see if it makes a difference.

You guys ever hear of this:
http://www.mototuneusa.com/break_in_secrets.htm

I'd be weary about going WOT so soon in owning my X. Give it a while before redlining.
:+1: I would break it in a lil longer.

You guys ever hear of this:
http://www.mototuneusa.com/break_in_secrets.htm

Interesting. But I think I'll still break her in easy.
But I do agree with...

Change Your Oil Right Away !!
The best thing you can do for your engine is to change your oil and filter after the first 20 miles. Most of the wearing in process happens immediately, creating a lot of metal in the oil. Plus, the amount of leftover machining chips and other crud left behind in the manufacturing process is simply amazing !! You want to flush that stuff out before it gets recycled and embedded in the transmission gears, and oil pump etc...

yea, its true that i need to break her in a bit more, but the ASC system shutting itself off after 10 minutes everytime is DEFINITELY not normal... so its off to the dealer we go! To better describe the sputtering, it happens around the 5000~redline range... almost like the gas is being choked... You can feel it as you mesh the gas pedal.

My guess is the X is running too rich and its choking itself at high powerband range...

Yeah, your issues (antics22) definitely shouldn't be occurring. Please keep us informed of what happens here.

In one of the threads here discussing one of the Evo X tuners, they stated that their car stumbled a bit up to due to richness.

yeah its too rich period

Interesting. But I think I'll still break her in easy.
But I do agree with...
Very good advice. I'm off to read everything, lol....

The ASC turning itself off is still persisting. Dealer is keeping the X over the weekend to troubleshoot.

i know we had alot of our temp workers putting low grade gas in some of the evos when they arrived (they no longer work here). so if yours came from tacoma it should go away with premium fuel.

http://www.motortrend.com/features/editorial/112_0603_technologue_race_performance/

here is the truth plz read for all break in questions.

well, ive learned to accept that the sputtering is attributed to the car being rich from the factory... but correct me if I am wrong. Shouldn't it NOT COME like that stock? Sputtering SHOULD NOT be considered normal. I see a class-action lawsuit in the works if this is indeed how a new car is being shipped out from Mitsubishi Motors North America.....

ASC problem is still unsolved. Dealer is scratching their heads....

http://www.motortrend.com/features/editorial/112_0603_technologue_race_performance/

here is the truth plz read for all break in questions.

"So it's your choice: Follow your owner's manual recommendations (which usually entail gentle driving at varying engine speeds and no towing for between 300 and 1000 miles); or pursue Web logic in hopes of gaining a racer's edge of added performance."

So what are we to take from this? He presented some arguments why the break-in period for smaller and lighter engines might be different than for larger and heavier car engines. But in the end the question is left unanswered.

My question would be, what is the danger in revving your engine at WOT to red-line before conducting a manufacturers' recommended break-in?

And how soon should we change out the oil the first time? And what oil and oil filter should we be using? Should we be using better filters that can filter out smaller particles? Should we be using synthetic oils, and if so which brands are better than others?

"So it's your choice: Follow your owner's manual recommendations (which usually entail gentle driving at varying engine speeds and no towing for between 300 and 1000 miles); or pursue Web logic in hopes of gaining a racer's edge of added performance."

So what are we to take from this? He presented some arguments why the break-in period for smaller and lighter engines might be different than for larger and heavier car engines. But in the end the question is left unanswered.

My question would be, what is the danger in revving your engine at WOT to red-line before conducting a manufacturers' recommended break-in?

And how soon should we change out the oil the first time? And what oil and oil filter should we be using? Should we be using better filters that can filter out smaller particles? Should we be using synthetic oils, and if so which brands are better than others?


Id use the factory OIL Filter just to be safe... which by the way, its the same exact one that they use on the 9's....

In one of the threads here discussing one of the Evo X tuners, they stated that their car stumbled a bit up to due to richness.

Yes that was my car at GST with CA 91 oct from 76. Since then i put in 4 gal. of 100 oct and went to Speed Element to get dynoed there as well. The sputtering was then non existant once running around 93 oct even though the car ran 9.5 AFRs on each seperate dyno.

Here is an interesting set of articles on oil:
http://www.carjunky.com/news/motor_oil/mom2.shtml

It appears this is an attempt to sell a certain kind of synthetic oil, but the information seems true enough. In particular, the advice to get rid of your paper air filter and replace it will a panel foam filter (that is washable and reusable) and an oil filter that traps smaller particles than normal oil filters. And obviously to use some type of synthetic oil.

well, ive learned to accept that the sputtering is attributed to the car being rich from the factory... but correct me if I am wrong. Shouldn't it NOT COME like that stock? Sputtering SHOULD NOT be considered normal. I see a class-action lawsuit in the works if this is indeed how a new car is being shipped out from Mitsubishi Motors North America.....

ASC problem is still unsolved. Dealer is scratching their heads....

You are correct.

This isn't the first time I've heard of sputtering on throttle up with the newer cars. I've been checking out the Mazdaspeed forums for a better part of a year and they have the same problem. Sputtering but at low rpms, low throttle..

Dont rule out the spark plugs. I had the same problems on my SRT-4 when I upgraded to a bigger turbo. Adjusted the gap and the problem was solved.

well from lots of thinking and talking to friends and all that jazz, slowly breaking in your motor seem like the best option and useing the correct oil that the factory tells you to use is the best way, well..... for one in texas if you change the factory recomended oil then you void your warrenty.

Dont rule out the spark plugs. I had the same problems on my SRT-4 when I upgraded to a bigger turbo. Adjusted the gap and the problem was solved.


but the car is stock and brand new. It should not be sputtering.. period.

yeah i think the factory is fing up a little, (pre evo jitters)

Dealers will likely be given a TSB to reflash problematic Evo's. Just keep complaining!!!

Has any other evo owner reported this? ( spluttering )

Has any other evo owner reported this? ( spluttering )

yep... i'm not redlining it anymore because of this, you can actually feel the power drop completely when the engine retards timing to prevent more knock.

btw, this seems to be only when running 91 octane...

yep... i'm not redlining it anymore because of this, you can actually feel the power drop completely when the engine retards timing to prevent more knock.

btw, this seems to be only when running 91 octane...

Actually AMS had this problem on their stock X as well. They ran 93 octane.

well i guess all you can really do is have warrenty fix it and use the highest grade octane you can get and from where you get it makes a diff also, i allways get my 93 oct at chevron because they have the best fuel out in the market, (tested and proven) so maybe you got a bad batch off gas?

1600 miles on mine and no sputtering issues... I've taken it up to about 6800 rpm, but as evoxco said, the top of the power band is 6000.

in addition, around last week, my ASC light started to come on... meaning that the car is shutting ASC off on its own. I am unable to do anything by pressing the ASC button. Once I turn the car off and restart it, everything is fine, but the light will come on again everytime about 10 minutes into the drive.

Definitely gonna get it checked out at the dealer....

I had this happen to me once just after I went WOT on it in a red light race (EVERYONE wants to mess with me, it's rediculous!), but after I shut the car down and turned it back on there were no problems, and havent been any since. That was about 1000 miles ago.

I have been slowly adding revs to my acceleration for motor break in. Getting closer to the top now. I am at a little over 600 miles, and the car is really breaking in nice. I can already feel quite a bit of difference in the bottom end. At least in responsiveness. There has been some discussion on whether or not there is an ECU break in. Hard to tell right now though. We need to get more cars over 1000 miles to see if things change. The ECU may be running rich intentionally for the first 1000 miles, but for some reason I dont really buy into this. It just seems more complicated then anything thats been done before on an Evo, so why start now.

I havent had any stuttering, stalling, sputtering, etc, but I do notice the ECU doing a lot of RPM adjustments at idle for no reason. Not sure whats occurring though. The rpms just occasionally seem to jump from 800 to 1100 and back, but in a very rapid manner. Much quicker then I think is even possible actually. Especially since Im not hearing the motor, but thats probably because you cant here it anyway ;) So nice, I think I have actually recovered some hearing loss caused by my VIII.

I had to tune the VIII today, and boy did it reaffirm that I made the right decision. The X is MUCH stronger down low. It makes the car feel so much faster, though its definitely not in the long haul. I would say for the first 300 feet or so though, this car pulls much harder. I have an accelerometer, Ill need to hook it up again and compare where the G's hit. In the VIII, I pulled 1.2g on launch around 4200 RPM's. I dont think I will hit that level, since I had a larger turbo with 400WHP, but I believe the curve comparison will show that we hit max g's much earlier. Christ, I should go do this know.

I pulled 1.2g on launch around 4200 RPM's


DAMN!!!!!!!!!!:+1:

Thats 1.2g in a straight line by the way, not taking a turn. Just want to make sure thats clear :) It would make me dizzy at times. Oh crud, I was off b .1 g. My apologies. Heres a pic of a 11.737 1/4 run at 117 mph and a 3.6 0-60. Ill do a comparison run in the Evo X and post it. Well, let me get past that break in first ;)

Thats 1.2g in a straight line by the way, not taking a turn. Just want to make sure thats clear :) It would make me dizzy at times. Oh crud, I was off b .1 g. My apologies. Heres a pic of a 11.737 1/4 run at 117 mph and a 3.6 0-60. Ill do a comparison run in the Evo X and post it. Well, let me get past that break in first ;)

Well, of course the X is going to feel stronger down low - it has a much better spoolup over your VIII (with larger turbo). Those times looks about right for a 400whp car.

My VIII still has the stock turbo so I can't imagine the X being as torquey down low (even with boost). One thing I love about the VIII/IX is the turbo lag followed by the sudden rush of power that makes you feel like you hit the NOS button!

Too bad test drives around here require credit checks and what have you. I'd definitely test drive one and compare it to my VIII.

Thats 1.2g in a straight line by the way, not taking a turn. Just want to make sure thats clear :) It would make me dizzy at times. Oh crud, I was off b .1 g. My apologies. Heres a pic of a 11.737 1/4 run at 117 mph and a 3.6 0-60. Ill do a comparison run in the Evo X and post it. Well, let me get past that break in first ;)


oh i knew what you ment, and once again.......DAMN!!!!!!!!!!!:drive:

well... heres the latest update, they found the source of the ASC light coming on to a "brake switch" It took them 2 days to source, so supposedly, that will fix the problem and I will be able to pick up my car today....

2) The sputtering problem has not been properly diagnosed as of yet, but they are looking into a "reflash" to see if that will cure it... Will update later today when I can "hopefully" pick up my car....

Scrath that. Just talked to the dealer and they still dont have the brake switch... How lovely.

keep us posted. i'm interested in seeing what a re-flash will do...