Auto repair

Need to do it myself, changing brakes on '97, 2500 chevy truck. How big is the job

I have honda civic 2000 lx. I had a check engine light on, so two months ago I replaced exhaust manifold, converter, and O2 sensor. Check engine light went away. It is back after 4000 miles. I did not change the second O2 sensor which is down in the converter. What could be the problem? Thanks

Besides checking the thermostat (replaced) why is my Jeep Grand Cherokee blowing cold air instead of warm or hot when I turn the heater on.:confused:

Yes, I have a 1992 Lincoln Continental with a 3.8 L injected V6. The problem I'm having is the transmission shifts good but slow and only if I accelerate it will shift smoothly into next gear. Do I have a exhaust problem or vacuum loss at the transmission. ...

God Bless You all, Merry Christmas and Happy New Year; If I don't chat with you all before the month is over with. Don't let nothing keep you from serving GOD.My Queastion, I have a 1999, 300m, which is out of timing, because of the belt teeth coming off. How do I set it?