Hi. My boyfriend has a 1996 Buick Century with only 27000 miles on it. We
went for emission test today and they said that there was a trouble code
present and therefore didn't pass. The code is P0133: Intake air
temperature circuit high input. I have been looking all over the internet
to see if this is a big thing and cost alot or is this something he can do
himself. And well I found myself here to see if you guys can help me.
Thank you in advance,
First of all, P0133 is a slow responding front O2 sensor and has nothing to
do with the air temperature. The heating part of the trouble code is the
O2 sensors used from the early 1990s have heaters inside of them to warm
the sensor and get the car into closed loop operation faster
This O2 sensor on most Buick/GM V-6's is at the rear of the engine bay near the center of the car located in the exhaust system and can be accessed from the top. I use a O2 sensor socket with the slot in the side to protect the wiring on the new sensor.
Cost for new sensor will be around $70 - $75. Risks of doing this job - the threads of the sensor sometimes bond to the manifold or pipe making removal of the old sensor tough. If you strip the threads during removal, you may be able to re-tap them using a 18 mm spark plug thread chaser. If you cant re-tap them you could end up buying a manifold ot exhaust pipe section.
When installing the new sensor, use a dab of Permatex 133K or equal high temp antisieze on the threads to make it easier to remove the sensor if you have to replace it again and tighten to about 30 ft-lbs.