Misfire

[yoss]

Hi everyone

 

I have a imported 1998 Version 4 imported STI 4door, i have developed a misfire between 2-4k rmp on full throttle, seems to occur on full boost and clears once above the effected rev range. once above 4k it pulls like a train but it seems to drop into a misfire whilst building boost. Ive cleaned the MAF/checked all silicone joiners, it has got iridium plugs/standard intercooler/standard recirc BOV and Ive cleaned all of the visible electrical connections. Any suggestions/common failures?? it has covered 160,000 miles with replacement head gaskets/skim heads 4,000 miles ago. never had any running issues before and  i am  scratching my head as to why its happening now!

 

Cheers

 

Yoss

[Tidgy]

checked the spark plugs? also could be a lead/coil pack issue

[yoss]

Yeah I will change the  plugs, its got Iridium  ones in at the moment.   (not a great fan of those) but shall fit normal NGKs and see how it goes.

  Thanks Yoss

[Tidgy]

NGK pfR6 for normal, pfr7 for tuned are the norm

[yoss]

Cheers will pick some up tomoz..

[yoss]

Well I bought a set of plugs, and some injector cleaner. Decided to use the cleaner first to see if it made any difference and after adding it to  a couple tankfuls  the problem has gone!!  Will fit the plugs at a later date. So all good..

     Cheers Yoss.