Toyota Repair: 1999 TOYOTA COROLLA CODE, exhaust leaks, o2 sensor

Question
Ted I have a PO 172 code My dauther says sometimes it bogs can you give me an idea were to start and what I should replace. I understand it is a rich condition.

Thanks for your Time Ted

Answer
The most common causes for this is an exhaust manifold leak, a bad O2 sensor(#1sensor in front of the cat converter)or a bad MAF sensor, in that order. Without taking it in to have it diagnosed I would replace the O2 sensor if there are no exhaust leaks at the manifold.