Niagara Gazette — •••
GABBY FROM MONTREAL: Our 2003 Chrysler Sebring has a DOHC sign on the engine. What does this stand for?
TOM: This stands for Double Over Head Cam (DOHC). Your engine has two camshafts, one for each cylinder head. Each camshaft controls the valvetrain on each cylinder head.
JOHN FROM SAN FRANCISCO: My mechanic says that my engine is sludged up and starving for lubrication. Can changing oil more frequently reverse oil sludge?
TOM: No, once sludge builds up it has to be cleaned out. Chemical flush products work on minor sludge problems. AMSOIL makes a good engine flush product that can be found at www.lubedepot.com. However, be very careful! If the sludge buildup is significant then there will still be some left after a chemical flush and the problem will persist. If this is the case, it will be necessary to tear down the engine. I have actually resorted to using hammer and chisel to clean baked-on oil sludge inside of a cylinder head. Good luck.
CHARLES FROM TEXAS: I own a 2004 Chevy Silverado extended cab pickup. The battery is new and it won’t keep a charge. I had it charged twice this week and, although it started the following day, the clock goes back to 12:00. When I turn the ignition on, sometimes it starts and sometimes it doesn’t. I am selling the truck so I don’t want to buy another expensive battery. I’m wondering if it would be all right to put in a rebuilt battery and let the person that buys it deal with the problem.
TOM: At this point I would suspect a rogue parasitic electrical draw sapping energy out of the battery when the key is off (not a battery problem). In order to track this down, a tech will have to monitor the battery voltage while eliminating each electrical circuit until the draw is eliminated. When the offending circuit is identified, then the tech must trace it out to find the problem and repair it. Otherwise, you will have to keep a full stock of batteries on hand. Or, you can just pass the problem on to the next owner. I guess it depends on whatever you can sleep with …