RPM Problem

[97 S14 VTC]

Alright, so im buying another S14 and this had a RPM problem. If it idles for 5+ minutes it wont rev above 2,200 unless you shut the car off and let it sit for about 10 seconds. the guy im buying it from replaced the cat with a test pipe and cut the sensor off. is this the problem? if so, can i drill a hole in the test pipe and mount it back it will be fine? thanks

[buentellomma]

check your mafs, it could be bad or dirty

[SoguRacing]

engine coolant temperature sensor

[97 S14 VTC]

the mafs is brand new, i know its gotta be a sensor somewhere. and the damn thing didnt do it today at all so idk. i just noticed that he cut the wire off the cat and thought that mite have somethen to do with it???