bad screaching sound while driving my 325

[kmarieheaton]

Just recently when I drive the car, it has a terrible screach while Im going down the road..like the brakes are grinding. But I tap on the brakes and it stops then starts again. If I ride the brake it doesnt do it. My mechanic checked the brakes not to long ago and said they were great. If the weather is cooler it doesnt do it as much. There seems to be no problems with the brakes as far my car stopping. What is this terrible sound and how can I make it stop? I have a 1988 325i. Hey, also, I have to get my bmw smogged. Nobody seems to think it will pass. Something about a catalytic converter..any thoughts? Would a tune up make the difference

[nino4588]

i believe the cat converter is great with o2 sensor and you will be good and for the noise i can be lots of stuff look at the rotor if its too old and rusty it will do

good luck

[kmarieheaton]

"cat converter is great with o2 sensor "..what does that mean? That the cat converter should be replaced? Do I just need to check the o2 sensor? The terrible screech was the bearings. Ball bearings? Im not sure..