match417

I have an 05 Evo VIII with a flashed ECU, HKS SSQV routed back into intake, Hallman Pro MBC, iridium plugs, custom exhaust w/o cat and some kind of aftermarket I/C.

I'm a mechanic for a living, i bought this car from another guy that did all of the mods to it, my clutch just went out, so I changed it (now it's a centerforce clutch/flywheel). And I went out of town so i had to let it sit for a while before I changed the clutch. There was a small problem before the clutch went out where the car would feel hesitant under load but for the most part seemed fine. I never could figure out what it was. Since my ecu has been flashed I don't think i can plug the analyzer into the OBDII port for a diagnostic. There is no check engine light on anyway. But now after getting back into town and replacing the clutch, today I tried to drive it, i made it about 7 miles driving fine, babying it of course because of the clutch being new. Now it revs fine when the clutch isn't engaged and there isn't a load on the engine, but when it's in gear, it doesn't go past 1500 rpm before it starts sputtering and hesitating. It only does it when it's under load. I had my boss look at it since he's been doing this for 30 + years and owned a shop for at least 14 years. He's just as lost as i am. It's not something I did in the clutch installation. I put everything back the way it was, if it was something I did in installation then it would have been like that immediately. Has anyone experienced this before? Or have an idea as to what it might be?

emagdnim8

iTrader: (9)

Let me know if you figure this out please.

Nightjoker7

What are your spark plugs gaped at when a engine is under load and starts hitting boost thats when the gap matters the most you could have a huge gap and it will idle fine its under load when it matters. don't have them gaped anymore then .26 and run ngk bpr7es. If its not that its probably a big boost leak.

Nightjoker7

I just though of another thing is your air flow sensor plugged in?

100%STEALTH

iTrader: (5)

you can try to clean the maf sensor

match417

the spark plug gap hasn't been touched, and it looked fine when i pulled out the plugs yesterday, the plugs are NGK iridium and aren't that old, i was gonna change them because i didn't know what condition they were in, they look almost perfect so i left them in.

i checked for boost leaks last night with a flashlight, the car is at my boss's house actually, i couldn't make it all the way to my house. He's cool with it sitting there.

air flow sensor is plugged in, but it could very well be a dirty air flow sensor, when i had the intake system open it's possible that dust and stuff got in there and was sucked past the MAF once everything was put back together.

Now that i think about it, this is a similar problem that I saw in a Talon TSi about a year ago, it needed injectors after sitting for a few months. But the injectors cleaned themselves out little by little after letting it run. But the evo ran fine for a few miles then crapped it's pants. So i doubt it's the same solution.

The thing i've been worried most about is the injectors because the ecu has been flashed and i'm pretty sure the injectors are flowing more fuel than they did stock. And stock injectors put out about 80 - 85 % of what they are capable of so they will last longer. And the car is putting out 385whp just with the stuff i mentioned above on stock internals. I don't know how much these injectors can handle but i hope they aren't dying.

quick question..does the EVO use a MAF or an MAP sensor? It's MAF right?

yangs4ever2008

Evo's use a Maf sensor buddy. If you have a aftermarket filter system, make sure your maf sensor is plugged in all the way and cleaned. For the Injectors issue you mentioned above. A aftermarket fuel pump will help keep your injectors balanced if yours is still stock(oem) somehow. When letting a car sit for awhile, make sure you fill up the tank, if not filled, it'll turn into bad gas and the car won't like it. Spark plug wires plugged in the wrong hole can cause misfires of cylinders causing you not to run on all four cylinders making your car run like shiet. It'll bog and have a hard time going uphill. Speeds are limited to and below 40mph. Long spark plug wire goes above; short goes below. If all else fails, go to your nearest evo tuner. Hope some of my info helped. G/L

P.S. Evo's will sputter and hesitate if a intercooler pipe is loose or popped off or doesn't have enough air going through your pipes. Make sure all clamps are tight and there is no damage to the pipes. Use t-bolt clamps

match417

what i was talking about with the injectors was the lifespan of them, all stock injectors that are produced aren't being used to their full potential and it isn't recommended to use an injector above 85% duty cycle, because it lowers the lifespan of the injector. So if whoever tuned it went over that to achieve 385whp then the injectors will fail sooner than they are supposed to. And I've only had it about 6 months so I don't know how long these injectors have been used on this tune. I played around with dyno's when i went through school, and learned how to tune an ecu both on paper based on engine specs and creating maps from nothing but my shop doesn't have a dyno, so i would tune it before I let anyone else do it if i had access to a dyno, i have to drive it across town if i want to tune it. But we didn't go over flashing ECU's in school, and i tried looking up the software to do it, but I can't find anything about tuning it, or what software to put on my laptop so I can plug into it, i've only worked with EMS's and I have an Autronic in my other car that is engineless right now . The guy I got it from said some EVO tuner came and tuned it. I wish I knew what he used to do it.

20gmr

iTrader: (7)

did the original owner put an intake on it?? you can still hook up a scan tool flashing it has no affect. go to www.openecu.org and download ecuflash. I recomend evoscan for a datalogging software although there are other options.

match417

yes there is an intake system, it's injen

gsrboi80

iTrader: (38)

You cannot test for boost leaks with a flash light. You need to make yourself a leak tester and charge the system. As your symptoms could very well be a boost leak

match417

I just looked over it with the flashlight looking for somewhere that the hose came off. It was driving fine for 6 or 7 miles, then just crapped it's pants after the BOV released pressure. It felt like a hose came off. That's what i was looking for with a flashlight..

Fast_Freddie

iTrader: (50)

Step 1- Proper boost leak test if you are unaware use google
Step 2- Downlog ECUflash and EVOscan and purchase a tactrix/limitless cable and datalog your car, if you went through EFI school you should know what you are looking at.

yangs4ever2008

hks bov = no good performance for evo's,
try putting the jdm mr dv blow off valve back on and see what happens; maybe the bov became faulty? something didn't work right? When a bov is on backwards, evo's will stall and idle incorrectly near a complete stop.

match417

the only stock parts i have from the guy i got it from are the stock springs. It's been dropped an inch. so to put a stock BOV back on i would have to buy one from someone online. i could try a craigslist wanted ad, but i would still have to buy it. and the bov is not on backwards. i took it off with the intake and put it back on exactly as it was when i did the clutch. i just need to find the time to check it out now.