Tw1in Sp1n

only codes are misfires in 4,5,6 and sometimes 2 and 3. I only feel the misfires and get the cel under wot and my boost gauge flutters around 11 or 12 psi. Giac stage 2+. found no leaks. swapped icms with a friend, no luck. replaced plugs a year ago with denso iridiums. what could it be!!! dont think that many injectors or coilpacks could have gone bad.

complacentsee

It could be the densos. Our coil packs are a matched design to the OEM plug types. Plus have differant design parameters IE: Internal resistances and spark gap to name a few. If you didn't gap them this could lead to an issue like this. As time goes on it gets harder to arc an oversize gap that is partially corroded.

I still suspect a boost leak. But would recommend you change plugs to OEM. Platinum plugs are **** good plugs anyway.

Tifosi

Both faulty EGT sensor or N75 valve can result in flashing CEL under WOT. You need to find someone local with a VAG-COM if you don't have one, to see what codes the car is throwing.

Allroady DungBeetle

Plugs. Try some cheap NGK coppers - Cheap test.

slowEURO

Can almost guarantee it is a boost leak. Doubtful that it's EGT, that would probably moreso lead to limp mode and no boost, not necessarily fluttering boost and misfires. I'd say you are in desperate need of a pressure test because a boost leak will lead to misfires on multiple cylinders. N75 could be faulty too but I feel that it is more than that because of the misfires, not just fluttering boost.

Tw1in Sp1n

I have checked vag-com. only codes for misfires. no egts, o2s, etc. Im not overboosting so its not n75. i have a pressure tester and have found no leaks. I used soap and water and checked all intercoler hoses, TBB, and all hoses by the firewall.

complacentsee

Since it sounds like you've ruiled out the usual suspects.

I still say it's the plugs. I replaced my denso plugs less than 1 year after I got them.


Drop the Denso Iridium. Our coil packs are very fancy and were designed with one plug manufacturer family of plugs in mind. Same reason it's not a good idea to run the fancy cross-fires, ect.

Tifosi

If that's the case, I agree with others here about it may very well be the plugs. IIRC, GIAC uses OEM plugs for their K03-SW, so I would go back to OEM plugs.

Tw1in Sp1n

replaced coilpacks that i had with my most common misfired cylinders and replaced the iridiums with oem plugs, so far so so good!! spiking at 17psi now instead of 14. no misfires or TC. knock on wood

complacentsee

Good to hear that it looks to be sorted out.