LBPS2K06

Hit the rev limiter on a mis shift last fall on a KW kitted 06. Since then car runs fine at lower (<4000) rpm but when it comes up to VTEC it spits and sputters and the AFR goes rich, like 10:1 and showing some knock in #2. Pulled plugs and they looked a little fouled so replaced them which helped but still not wanting to rev past 4k. Replaced the coil on #2 and that got rid of the knock but still wont go past 4k. Car has under 59k miles on it, so going to adjust valves next. I cant imagine the valve train took any damage as it runs fine at the lower RPM. Next logical step I guess is the VTEC solenoid. Anyone have any thoughts?

Rob

starchland

What rpm and gear did you shift from?

bgoetz

Did you misshift or just not shift and bang the rev limiter? If you misshifted the rev limiter won't keep the car from overrevving and messing up the valves. My guess is a bent or burnt valve.

LBPS2K06

The fact that it runs perfect under 4k leads me to believe its not a valve though.

maranelloboy05

Do a compression or leakdown test?

s2000Junky

Spark blow out? what are the plugs gapped to? This is not uncommon, however usually this tends to happen a bit higher in the rpm range where fuel duty is higher putting more demands on spark. If the gap is too big, the spark will get flooded. Ambient temp and 02 feedback will change fuel demands and cause break up if was close to threshold previously. Generally a good plug gap for a 400whp supercharged set up is about 0.22-25.

LBPS2K06

Compression test will be coming. Changed out all the plugs. Put new coil in the cylinder that was showing knock.

steelers743

what kind of tune are you running? Sounds like a tune issue or that could help show the issue. If the engine is showing knock the CPU will retard timing a ton

bgoetz

Did you misshift or just NOT shift, that is the key question. If you misshifted by bet is that it IS a valve.

LBPS2K06

Corey at Slowmotion did the tune. It was a misshift. Hit 3rd from 4th instead of 5th but not at a real high RPM. I just cant believe it would run as smooth as it does under 4k RPM if it was a valve but will get it checked out.