Evo breaks up on acceleration once...

[MISHI]

Strange issue: I had installed a mishimoto radiator and some bpr8eix plugs back in november 2009.

Car ran good till May 2010 where the car would give me a heavy misfire on first or second acceleration. But the thing is, the car would do so and then run fine all day boosting.

And it does so once you first start the car for the day or leave it off overnight. The car could be warmed up fully and driven for hours... when you first boost, it hesitates, then on the next run it pulls fine.

Regapped the plugs to 0.5mm and same issue: Checked for error codes and nothing came up. Check for gasket issue and there aren't any... decided to replace the plugs with the OEM ones and it ran fine from May '10 till today (10 months)...

Car wasn't driven for a few days and we had a LOT of rain. So decided to go out today. Now it was a bit colder than usual with the weather so I took my time and drove around normally for about half hour or so. Then when I Hit boost and the thing hesitated like hell... once. Then ran fine all day afterward.

I'm still not getting any errors/ water missing etc... could it be the car just being "too cold"? I duno if the radiator as it's better at cooling than the OEM one probably making it not achieve op temp...

Any input would be appreciated.

[crazybalhead]

Even after the stock gauge is saying "warm" the thermostat sisn't even open yet. I would give it a five minutes after warming up and then see what going on.

[MISHI]

That's just it... you could leave it warmed up for more than an hr and it still does it when you drive...

[GEAR_HEAD]

spark plug wires?
injectors?

[crazybalhead]

next question...you havea boost gauge?? You sure your wastegate not sticking and you are overboosting? Causing a fuel cut? And when it boosts and realeases the first time, it's ok after?

[MISHI]

nope car runs 20psi. Boost runs up almost to 20psi and hesitates the first time... then it's normal. The wires and injectors etc are fine. This only happens when the car is left overnight or not driven for the entire day.

My theory is that it started happening not too long after the radiator went it and I have noticed the temp gauge has been slightly lower than when i had the OEM radiator (which BTW was damaged). I want to feel with the car being overnight and especially on cold/ rainy days it's not getting to the op temp even under normal driving... I don't really have far to go with it so usually it's not driven hard... only now and again I'll give it a boost. Also the ECU is ralliart sports ecu mapped so I dunno if that combined with the cooler temps from the rad have anything to do with it.

What I may try is to warm the car for a while again but this time wheh the gauge gets where it usually is, I'll run the throttle up to about 2500rpm for a couple mins and see if that helps. But today isn't as cool as yesterday so it probably won't do it at all.

[crazybalhead]

Maybe the thermostat stuck open then. You have a water temp gauge? That will confirm.

[MISHI]

nah no gauge...

Tried it today and it worked fine, but today was warmer than yesterday (my god I sound like I'm in a temperate country don't I?)

So maybe that's just it... will keep an eye and see I'll also test with evoscan on the colder morning and see.

[Porn Star]

Bun it dong and claim insurance.

[crazybalhead]

Bun it dong and claim insurance.

WDMC....Just so????

[MISHI]

third party don't help me there.

[Rudman]

Dare I say it........coil packs?

[thatguy3832]

Third Party Fire and Theft. then bun it dong?

[MISHI]

Nah not coilpacks... and no I ain't burning down the car.

Seems to be a problem for some on evolutionm.net with colder weather as well... so will wait for another cold morning and try it.

[Silvermike]

coudl be coils, if it is check me, i got an extra set.

[MaelstroM]

I think it is the plugs. I used to have probs with that with my car on cold days.
It would break up like the first 2 pulls and them work fine.
I lived with it and then bought the Sparktech ignition.
No probs after that. Hot or cold or whatver.
Try gapping smaller?
Just try 7s on a cold morning?
I not sure.

[W2J]

^ tell the op where to get Spark Tech, Mishi 9055001 RA has issues with the warm up tables, maybe you should let somebody who knows about tuning look at it for you.

[MadCrix]

.5??? whey

mishi i running 28 thou

try smaller gap, also try a stock ecu and see

[W2J]

^ you know how small .5mm gap is even on cars I have tuned with 30+ psi I never went that tight.

[Silvermike]

^ he thought it was .5 inches im sure.

Its clearly not a plug issue...ure right in saying it could be something with the tune. If not, maybe its fuel related. You got a properly working pump in there? filter good? FP good?

[MISHI]

Everything's running good. no issues with the pump, filter... nothing. It really could be the tune. Car had ralliart RA 560649R1 flashed... got the car that way.

I haven't had a colder night since the original post and haven't had an issue at all, but yeah... probably sometime i'll organize to have a tune.

On the plugs though, the 8's I gapped to 0.5mm... the stock 7 plugs were 0.6mm as per manual.

[White CZ4A]

Sounds like an injector problem to me.

Similar thing happened to me and it turned out it was faulty injectors.

[W2J]

.5mm = .019" u running big boost

[MISHI]

Well it was at 0.6-0.7 but I put it at 0.5 when i was troubleshooting. It did help but not much. Then of course I ran the stockers back in.

[Dave]

as your coils age, the ability to bridge the gap and produce a spark decreases but as they heat up it should get worse and miss fire more, hence the reason to maybe reduce your gap as coils age

having said that, i ripped out my 2 dinky coils and even dinkier wires and ran some msd blaster coils with some of my old ngk wires, used my digital 6 box and realised i needed a distributor so i drilled a hole in the valve cover and installed an old ess arr tweeny distributor i have lying around, engine never ran so good

[MISHI]

Did you add the VVL as well?

[MadCrix]

no he lent me that feature... i ordered a harness to hook it up, i eh wha cut my stock wires