Hi, New to the forum
new to the evolution world(came from the 1g DSM world)

my problem. under WOT in any gear i can feel the power surging in and out and once it gets to higher RPM around the 4-5k mark it starts breaking up(hitting a wall intermittently)

progress so far
Gapped plugs to 022(thats what they were at when i pulled them, also were a little lean but not to crazy)
tightened all intercooler pipe clamps/checked for loose vacuum lines
and i reset the ecu.
after doing all this i took it for a rip and it was stable all the way through 1st 2nd 3rd. no lags no sputters ran great. but after 20 mins of light driving and idling through stop/go traffic. under WOT it had slight blips like a miss but not as bad as before just like split second surge and its back to full power.

bought the car used. it has the "cone filter stuffed on the MAF" the factory parts and airbox are in the mail to return it to stock.

things im going to do in the next couple days.

boost leak test
compression test(if i can find an adapter)

only other thing i can think of is maybe i got a shot of bad gas
in the tank

wishing i had a datalogger or more info.

any help is muchly appreciated


2008 GSR 112000kms, full factory exhaust, ghettoed out intake, 94 octane

 

First off -

Are you tuned for that intake?

If you aren't sure, get your car protuned ASAP. (that is more than likely your issue if you aren't tuned) If there are no great tuners in your area, you can also get an e-tune for your car which would be better than nothing.

Past that, if you are tuned, then you could start small and replace the fuel relays which is a cheap test fix, and is also highly recommended for EVOX's prior to 2013 I believe. (Those are known faulty on older EVO's)

http://www.kozmicmotorsports.com/fue...2008-2014.html

These are highly recommended to replace in any EVO prior to 2013 I believe (Someone correct me if I'm wrong)

Past that, are you

 

thank you for your fast response. im unsure if it has been tuned. so putting the stock intake is my best bet other than a pro tune? and i have a handfull of random relays in my glove box that came with the car. wondering if they switched them out already. im gonna order them right now anyways

 

Yeah if you're not tuned I'd do that asap, that will jack up your car.

Good rule of thumb - If you have any modification that changes air volume, or flow, get the car tuned for it. (especially on a turbo car. On an EVO you probably didn't break anything. If you had done this on a Subaru you'd be looking at a 7k repair bill for a new motor)

Aside from that on your 08 you may want to have your timing chain checked for stretching, which is an issue with an 08 up to 11 EVO. Better safe than sorry with that imo, a skipped timing chain is no bueno.

Good luck with the car!

P.S. That Komzic place above also e-tunes so they could help tune your car if you are too far from a tuner in your area.

 

Check your fuel pump relay. The stock fuel pump relay 2008-10 had problems and go bad. They don't allow switching between low and high voltage causing the car to run lean under boost. That's a common problem. I switched my relays to the ones offered by kozmicmotorsports.com. If you do a search, you'll find what I'm talking about in better detail. I had a k&n 3" intake and come filter and a 2.5" uicp before tuning mine and I never had a problem.

 

UPDATE
Installed OEM air box and filter
put the fuel pump relay into the horn relay position and the horn didnt make a sound but i could hear the relay clicking.
so i put a big blue mistu relay in there. i havent ran the car yet i was hoping for input on using a big blue relay in its place.
i also unplugged the fuse #2 for 20 mins and replaced it.

 

Hold up there

Research the fuses before you start switching things. I believe the blue ones were the bad ones and black are good?

Google it

They will have a part number so you know what you are dealing with...

 

blue are better than the orig short black. not the best yet. but an improvement. i ordered some proper ones from the site you linked.

 

started car after ecu reset. let it warm up to operating temp. then drive at light throttle for a bit. did a WOT pull and it was smoother than ever before. idling smoother. even starting off is easier in 1st gear. total improvement. the previous owners air intake job = fail. and fuel pump relay = fail.

so far id say its resolved

 

Cool glad to hear it!!

If it has any stumbling at all after the new relays you get in are switched out it might be time to see if there are any other aftermarket parts that were installed and not tuned for.

 

Depends on which black. Might want to double check. But if its the older version, you're correct. IIRC it's green, black, blue, black (final version).

 

Do a google search for "Evo x fuel pump relay" and it'll give all the info you ever need on fuel pump relays, part numbers, and all that. http://www.kozmicmotorsports.com/mitsubishi-evo-x/evox-fuel-system/fuel-pump-relay-and-kit-for-mitsubishi-2008-2014.html 👈🏻 is where I bought mine from.

 

Running smoothly. But got odd compression numbers.
Details; car warmed up to operating temp. All plugs removed and injectors d/c.

Left to right. 120, 130, 120, 115
cranking 8 turns per test. These numbers are the 7th turn. Turn 8 didnt move the needle. I didnt have any oil to throw in to check rings/valves. But the pressure held at those numbers. The car has 2000kms of warranty on the engine left, and two weeks. So im thinking the fuel pump relay was burnt long before i got the car. That combined with the cone filter that was on for an undetermined amount of time. Im thinking this motor took a beating before i got it last week.
Side note; I did the test 2x per cylinder

 

Glad to hear it's running smooth, that blows about the compression though. As long as it's in the minimum specs you should be good but no one wants to buy a running car just to have to rebuild it.

 

Does the car have an open dp or tp? I had the same issue when I went to Cobb Stage 2, and thought it was my fuel relay or pump, but got a boost control solenoid and problem fixed. Runs great and my data is clean.