Under hard acceleration my car has started to pause for a second before kicking in, this occurs at about 5000r.p.m
Its a classic WRX(94)scooby with no mods except an aftermarket exhaust (cat still in place). Any help would be much appreciated.

 

check your plug gap should be about 0.7mm and your coil packs. had similar prob went away after replacing the plugs and coil packs.

HTH

 

sounds like plugs to me too, check gaps or replace em if it hasnt been done for a while, stick with NGK platinums and u wont go far wrong...