I own a 2002 Ford Taurus SEL that I purchased new. It was driven 41,000 miles. This year I have noticed a large drop in gas mileage for city driving. It was billed as 20 mpg city, but now I’m closer to 10 miles per gallon. My mechanic has checked the usual things, sparkplugs, wires, filters, and everything looks good. What is he missing, if anything?
QUESTION: I own a 2002 Ford Taurus SEL that I purchased new. It was driven 41,000 miles. This year I have noticed a large drop in gas mileage for city driving. It was billed as 20 mpg city, but now I’m closer to 10 miles per gallon. My mechanic has checked the usual things, sparkplugs, wires, filters, and everything looks good. What is he missing, if anything?
ANSWER: Every fall I get letters from readers complaining about a loss in gas mileage. This happens for a couple of reasons. First, the difference in the winter blend gasoline will lessen gas mileage. The winter blend is designed to fire off faster in cold temperatures. Second, the engine will run longer in the closed loop mode because of the colder engine temperature. In the closed loop mode the engine operates in the preprogrammed computer mode. The engine runs richer and the transmission will sometimes not shift into overdrive or top gear. Oxygen sensors also get lazy with mileage and more noticeable in the cold temperatures. Engine oil also thickens and causes more drag on the engine. This is where full synthetic oil can also make a big difference.
QUESTION: Hello, I hope you can help. I have a 2000 Tahoe. I have been to four garages and no one can figure out the problems. My check-engine light came on and I took it in and they said it was the 02 sensor. Replaced it but light still on. Took it to another place, 02 sensor. Replaced that one. (I believe there are four in a Tahoe). Took it to an electrical specialist who said the 02 sensors are bad. Explained I had already replaced them. He told me I needed only GM parts. I replaced all four with GM sensors and the light is on again and now the check four-wheel drive light is coming on. Got any ideas? No one seems to know and I have already spent a fortune on this mess!
ANSWER: I see this problem quite often. Just because there is a trouble fault code does not mean the part is bad. The trouble code is relating to the circuit that has the problem. It could be anything from a broken wire in the harness, blown fuse, or faulty ECM. On some cases I have seen the small electrical connector corrode or pull slightly out of the connector. I suggest you find a technician that has knowledge of your truck. As for the four-by-four service light, this is often seen on GM electronic transfer cases and not connected to the oxygen sensor fault codes. The circuit will have to be checked. As for the use of only GM parts that is not true. There are many good after-market brand parts on the market that meet or exceed OEM parts.
QUESTION: The extended warranty on my 2004 Acura TL will expire in May. I have noticed a subtle vibrating on the steering wheel and the driver’s seat when I am idling. When I’m driving I don’t notice anything wrong, but when I stop, I have to take my hand off the wheel because it is uncomfortable to hold. It also vibrates when I am in neutral and reverse but not as much. Six months ago I mentioned it to the serviceman at the dealership and he said that it will be looked at during the timing belt service in May. This includes replacing the timing belt, accessory drive belts, water pump and gasket and other basic things. This in itself is expensive, so if there is something else wrong I want to get it fixed under the warranty. Should I get the timing belt service before the scheduled date to narrow down the potential problem? That will give me time to use the warranty. Do you know what this might be and could it be done under the warranty?
ANSWER: I would look at the engine mounts and fan belt driven accessories. I would also look at exhaust hangers, brackets and any shields. As for the timing belt, that should be replaced per recommendation of the manual. This car has multiple engine mounts and at least one is liquid filled.
Junior Damato writes regularly about cars. You can send questions to him care of the Old Colony Memorial, 182 Standish Ave., Plymouth, MA 02360, or e-mail email@example.com.