Thread: Car running bad, unsure if trans or engine

I drove for about an hour, no codes hit. I'm going to clean the MAF tomorrow, amd make an appt. to get my cat replaced this week.

dont just assume the cat is bad yet.

You should do tests befor you just assume stuff.

take the upper o2 sensor out and take the car for a short drive, yes it will be loud like a tractor and will throw a code, if the car runs better when doing this test it show that the cat is plugged up because the o2 hole is open its letting all the gases that cant normally escape get out.