I just recently decat after installing HKS 272.

Not sure if decat is the cause but the car felt very lethargic from 1k-2k rpm...I could just pump the gas pedal within this range and the car response very slowly.

Comments....

 

Exhaust leak. That's the exact symptom I have when there is a leak.

 

Normal after cam install.

Your powerband has shifted upwards.
I bet it's a whole different animal after 4500 rpm's full boost though.

Get tuned and it will even pull stronger.
.

 

Can you elaborate? Typically where will the exhaust be leaking from? This is before boost.

 

+1 to the cams, although if everything was fine before you put in the test pipe I guess it could be an exhaust leak... although its pretty hard to mess up on those 4 bolts as long as you used a good gasket..

 

Guys, you won't believe what's wrong...not exhaust leak, not tuning....it was the spark plug cable that is faulty...although it seems to be ok at idle...and able to rev, but once under load...it screw up...it is a ralliart too. Now revert to stock...everything is back to normal...What a JOKE!!!!