The car is being a pain in the *** for the last few weeks...

The car has the following :

• 1.0 bar tune
• Catless Exhaust
• New Irridium Spark plugs (Just Changed)
• K&N Air filter
• Twin DV's silicone F-hose
• New MAF

Its been a bit stuttery lately so I first changed the AFM, no joy... next I changed the plugs and it was great for a day, totally different car but now it will only boost to 0.4 and misfires BAD as I come on boost.

After I get past about 3k and slowly put my foot down then floor it the car doesn't misfire it pulls all the way to redline peaking 0.5 bar but no more than that.

Codes i had prior to this was ones relating to the car running too rich (due to exhaust) and now several misfire codes if I leave my foot down long enough.


I've read dozens of threads now and the only last thing i can think of to change is the coil packs?

 

What's the gap on the plugs?

 

Also, what are the codes and what cylinders?

 

Not sure of the gap... they are NGK Iridium IX Spark Plugs BKR8EIX - (2668) and like I said for the 1st 200 ish miles after i done them the car was an animal !

I cleared the codes because i cleared them straight away but I remember seeing a 4 and a cylinder 6 perhaps too...

 

"but now it will only boost to 0.4 - to redline peaking 0.5 bar but no more than that" sounds like possibly a boost leak? I had similar peak of .4 -.5 found had snapped drivers side actuator rod?

 

The spark is blowing out.. You are getting misfires in your torque peak where the cylinder psi is the highest. Make sure there are no cracks on your coil packs, pull the boot off that goes to the spark plug. PS misfire will not let the car make boost...

 

Ok this is making sense, i did find a boost leak when putting the plugs in (passenger intercooler pipe was loose) but now it looks like ill have to take the rear end to bits again to check coils ! i might as well just get x6 coils (one was slightly cracked when I did the plugs last week) ....

Will report back once if done it.

 

https://www.6speedonline.com/forums/...ant-996tt.html

Sounds like a spark problem. Look at Vividracing's dyno post here. Sounds like what is happening to your car.

 

But i have pre gapped plugs the coldest i could get !

NGK Iridium IX Spark Plugs BKR8EIX - (2668)

 

Gap is about .8mm (.032"), NOT 1.6 mm as the shop manual states. I wouldn't try to adjust them if the gap looks reasonably close. Mine were about .025 -.032"

 

Definitely do a boost leak test from the turbos and after that is verified/corrected and still have issues, change plugs. If it was coils it would most likely be on one cylinder, but I would do them anyway. The plugs you have are a little wide on the gap.

I would run plugs that others are using or be sure you know what to gap them at. Ask me how I know. :-)

 

I agree with everybody here. It's either a) boost hose leak. If you dont clip them in just right they can pop out, sometimes just partially. Pull on them all make sure there seated fully.
B) your plugs are not gapped properly. You can't go by that there gapped properly in the package. Plus you have to actually make them closer than what is factory. Trust me I had to do this myself.
Chances are those are your issues, talk to your tuner and ask them what gap to run. This will cost you nothing but your own time. That's what I would do. Good luck.

 

coilpacks

 

Too cool of a plug will load up than misfire.

 

Sounds to me like spark plug blowout, and/or weak coilpacks. But i'd also do a boostleak test as well if your in there, why not!