GTR 33 idling funny

[coach]

Looking for some advice

My 95 GTR 33 starting idling funny the other day. It idle's fine until in warms up, then the idle drops about 400 rpm, then goes back up to normal. It also sputters when cruising at a constant rpm, it pulls great.

Looking for help

Thanks

[Skym]

O2 sensors. The rpm going up and down is what a faulty o2 sensor does when totally gone (stock ECU plays a part in that). Basically o2 sensor is lazy when switching from rich to lean, lean to rich and get a popping sound from exhaust (flames from exhaust), as o2 sensor makes ECU make engine stay too rich for too long. Rich = revs drop, lean = revs rise. The o2 sensors are meant to be checked, replaced every 40-60,000kms as part of routine maintenance.

[coach]

thanks man

[coach]

are there any compatible o2 sensors for a GTR 33 ? or do I have to get a special o2 sensor ?

next question, without a test which one is it most likely to be ? how many on a GTR 33?