P300 CEL on evo IX
 

Just to start off, I know this has been discussed 3452345 times, and I did use the search, however, couldn't find any good solutions and wanted to bring this topic back.

First off, i have almost 20k miles on the car, and the mods are TBE+Intake+HKS BOV.

Took it to the dealer this morning and they tried to reflash it and said that it didn't need to because the flash was made for the 03-05 models and the program seems to already updated, however, my intake and BOV could be the cause for the multi cylinder misfire code due to the possibility of over boosting. They checked the spark plugs and they were fine as well. So now I am planning on putting back the stock oem BOV (if you have one for sale then let me know) and maybe the stock air box (if you have one for sale then let me know) as well to see if that is the cause.
My questions to you guys are:

1) What do u think about what they told me?
2) What do you think the real cause/solution is?
3) if I was about to put it back to the metal BOV, what are the parts that I should be looking on buying ? (I got the HKS bov with the car when I bought it)?

Thanks, and I appreciate all of your comments.

first of all get rid of that horrible hks bov thats the first thing invest in a aps twin. According to mellon that p0300 code is a misfiring code for CAMS. the code is just a annoying code that means really nothing to the user. you should just get your tuner to delete it from the ecu and problem solved. when i bought my car i had a couple Cel i cleared them all the last one i had was the annoying p0136 :( i ending up doing the non fouler and having to buy a used rear o2 sensor and install it. CLEARED ALL THE CELS RIGHT. lol i was happy then it came back on i got it check out buy autozone and its the stupid p0300 never got that code before ever it comes and goes my car runs PERFECT and its never been tuned :p me and mellon are planning a massive build at that point ill tune it. he knows everything thats been going on with my car i told him about that code and in his words its a bs code that means nothing just triggers usually when you have aftermarket cams. Cause you to bring it to the dealer so they can find other problems. I dont have any cams in my car that i know of BUT I MIGHT and just not know it. So dont worry about it just please change your bov and get your tuner to delete it frome the ecu it will not be missed

Get rid of the hks bov.

exactly get rid of the HKS BOV and find a stock MR BOV...thats what i'm using and i run 25psi daily with no leaks...

Ya that's what I am thinking of doing is getting rid of that HKS and put back the stock DV on. Its horrible at mid throttle, the whole car studders, does the twin aps do the same ?
Thanks guys!

update!

the code comes on and off whenever it feels like it. has anyone encountered such a thing in the past?
one thing i have changed/modified tho is that I originaly have put a 3'' tbe on the car and been noticing some metal contact noise, i looked under the car and there was a small metal bracket under the body right by the drive shaft coupler that was basicaly hitting the pipe when Iam either idling or shifting , causing that noise, i bent it a little bit away from the pipe, so now i don;t get that noise as much as before. My thinking is that could the engine be sensing the vibration/metal contact from the bracket to the pipe and think that its misfiring? please tell me iam right..lol and that would solve the issue.

Thanks

i answered your question above pm me your phone number now we can talk right fast

pm sent!

update!
the dealer looked into it after putting back the stock exhaust and ucip. and it was a bad injector seal that was trigging the general multi cylinder msfire and the cylidner specific one itw as on.
thanks for all of ur help guys!
so it wasn;t the ucip with the vta hks bov. <<< i have those for sale now if anyone is interested.