red90GT

90 GT..although it is running great after a good seafoaming..the engine feels like it holds back in 3rd gear about 2400rpm unless i give it more throttle. 4th gear same thing. now it still has stock headers and stock H with all cats. 180000 on the clock and the cats are original. could this be where the hold back is from? if i bought shortys and a catted H pipe could this solve problem? all sensors have been changed and codes are all clear. maf cleaned and tps set at .98. new plugs everything like i said the motor doesnt hesitiate at all it just seems that under load light throttle it holds back. thanks

notchbackmatt87

ever do a tune up. plugs cap rotor, wires? fuel filter? air filter?

red90GT

yes. although i am using the autolite platinum plugs. CAI bbk month old. msd 8.5mm wires with cap and rotor. blaster coil

notchbackmatt87

could possibly be a clogged cat or partically clogged cat.

red90GT

thanks. i never ran into an experience cat related. it doesnt smell like anything or set off the SES so i didn't know. thanks for your fast replys man..

mjr46

loosen the exhaust and run it like that and see if the lack of power clears up.. or pull out the o/2's and run it like that..and yes the car will still run without the o2's in...your just doing it for diagnostic purpose so it won't harm it for the short time up the road and back you do it for