xviper

It's to reduce the amount of hot air sucked into the airbox, but since you don't have the stock airbox, this does not apply to you.

Anyway, this is what he's talking about:
https://www.s2ki.com/forums/index.php?showtopic=70356

NorthCyprus

Thanks for the post and the link Xviper, i think that might help me but not solve the problem. I know that my standard s2k should have nothing wrong with it, i know it's one of the stock parts that needs to be fixed in order to solve the problem. I'm trying to find out which one it is. I know it's not something to do with the ECU bcoz 2 ECU cant do exactly the same problem can they? , same thing for the other parts i have changed! I'm trying to find out which part is faulty. I'm sure theres a faulty part. What do you think about replacing the 'charcoal canister'?

xviper

I suppose it's a possibility but I'm a bit scepticle. This cannister is a fuel recovery device that helps to put fuel returned from the fuel pressure regulator back into the fuel tank and is part of the emissions control. If there was something wrong with it, you would get a CEL, which you say you don't have. Whether or not you have pressure or vacuum in the fuel tank shouldn't make that much difference to the way the engine functions. People who have had a loose gas cap have only noted the CEL. The engine still runs as is does when the gas cap is tight. I believe you are at a point now where you are running out of options on what to do next, so if this is something you want to try, then go ahead. You just never know.
BTW, here is what this cannister looks like:
It's the thing with the honeycomb pattern on the end of it.

jyeung528

maybe the clutch is just slipping on occassion.

TrueDrezzer

You did mention that the car was running rich and that your fuel consumption is atrocious? Faulty O2 sensors. Perhaps have an emissions test done to see what the lambda-values are. Maybe they were damaged when your single-output exhaust was installed.

BTW, European octane ratings are different from US ratings. The S2k requires 98 EU octane = 91 US octane. 100 EU octane is about 94 US octane. I've run the car once with 95 EU octane without problems for a short time.

///Robin

TwiztedS2K

Would the clutch slipping cuz this problem only during acceleration, and also, would the clutch cause it to idle incorrectly? Im clueless as well, I am having the same problems.

xviper

Thank you for this. I kinda thought that this was the case when I mentioned this on page 1 or 2 of this thread. He did say he was using 90-95 Octane. This would mean that he was using GARBAGE fuel. I am now not surprised that his car ran the way it did. I think out of all this, he has changed all that stuff for nothing except to get new parts. He even stated that his friends who ran 100 Octane had no problems. Only he, had problems.
Cyprus, now that you've switched to 100 Octane, have you run it long enough to flush the garbage gas out of the system? And have you now been running with 100 Octane long enough to tell if the problem still persists.

TwiztedS2K

Hey XViper, question..... I am having the same problem as Cyprus, and I noticed we both have single exhaust, whcih was custom made.....I have been running 93 octane (US) ever since I got mine. Could the single exhaust maybe screwed up the 02 in a way that the fuel intake could be messed up. I know that if there is not a enough backpressure, the 02 might cause vtec to not kick in and whatnot, could that have anything to do with it? I have parked mine because the problem is so bad.

xviper

I somehow doubt this. The secondary O2 sensor is in the cat. If you left this on, your single exhaust should have no affect on it. Even if you put on a test pipe and burned the crap out of the secondary O2 sensor (if you didn't do a mechanical simulator), it would still have no effect but to give you a CEL. It's the primary O2 sensor in the exhaust manifold that tells the ECU how to run the engine. Putting on a single should not affect the function of this sensor either. Lots of people have single systems and have not reported any misgivings. They only report more power. Something else is going on with your car that is yet to be discovered.

mxt_77

True... so maybe he should check that.