The car runs great driving around town, but if you go WOT in second, it appears to be missing. The car is throwing no codes or warning lights and does not indicate a lean condition on AF meter. I do not believe it is in the tune, since it is the same tune I’ve been running for 8 or so months. I have so far disconnected battery, cleaned TB, MAF and Air Filter all of which looked cleaned. This did not fix problem, I then inspected the 4 random sparkplugs, which appeared normal. I will try and attach pic. My intended next step is to replace sparkplugs, they have ~8K miles on them. With it being kinda expensive to replace them is there anything to try before replacing. I did also turn of TCS to verify that that was not the cause.
Thank You for your help.
The car has ~24000 miles on it.
Currently running 3 1/4 inch pulley with updated tune.

 

Are you using the stock intake tube?

 

seems like you are on the right track and plugs might be
the next thing to consider. if it feels normal when WOT in
third gear, maybe you are getting a little belt slip in 2nd?
if it's not the belt, then i agree with trying new plugs (with
.032 gap), next.

 

Have you changed the fuel filter lately? Just a thought.

 

Dumb question..but is traction control turned off?

 

Have you determined proper fuel pressure at WOT?
The proper AF would indicate proper pressure...
Are you sure BOTH pumps are running?
Once again, the AF is good during the missing.
How about a nighttime inspection of the
spark plug wires for signs of leakage?
The OEM coil is known for high RPM missing as well...

Maybe check the mounting hardware on your coil pack bracket?

 

I ask because I was around your power level when I found the stock rubber intake tube starting to pinch shut under WOT. It would cause the engine to cut out.

 

Thank you guys for the input.
Replaced fuel filter 4-500 miles ago.
Still missed with TCS off
It has the upgraded intake tube that cam with breenspeed's stage 1 kit.
It could be belt slip. I didnt mention it does in third, just doesn't do it has much.
I'll give sparkplugs a try. I expect I'll go with HTO, unless any other recommendations.

Thanks again.

 

You are supercharged. Its the plugs.

 

Can you do some data logging with your handheld and send the info to brenspeed?