Dear Doctor: I own a 2002 Mercury Grand Marquis and 2000 Honda Accord. They both require 5W-30 engine oil. I acquired a couple of cases of 10W-30 full-synthetic oil. Would the different viscosity hurt the engines of the Accord and Grand Marquis, or alter the emissions tests? Paul
Dear Paul: Both your 2000 Honda and the 2002 Mercury vehicles are out of factory warranty. If I were the owner of these vehicles, then yes, I would be using the full-synthetic oil. It flows better than the petroleum-based oil. Another factor is both cars have mileage and normal internal wear. The extra oil viscosity can actually help the engine sealing. Oil lubricates, seals and cools the engine. If the cars were new and under the factory warranty, then I would inform you that the use of non-recommended oil could void the warranty should there be internal engine failure. The use of the oil will not affect the emissions tests.
Dear Doctor: I own a 2006 Chevrolet Malibu Maxx. The dealer had to replace the radio under warranty and I also had to have the steering wheel audio controls programmed for the new radio. The car still has the original battery, but it is weak and I want to replace it. If I replace the battery will the steering wheel controls need to be reprogrammed? Charley
Dear Charley: My word of advice is that you should not disconnect the original battery to replace it with another in the majority of late model vehicles. First, there is the risk of loss of computer memory and drivability — and in some import vehicles the automatic transmission will not shift and may need reprogramming with a dealer’s scan tool. Secondly, the radio security may lock out the audio. Some factory alarm and power window operations can also be affected. There is a solution. A company called EZ Red (among others) sells a power pack that powers the vehicle through the ALDL connector under the dash. Then when you go to make the battery selection, make sure to buy the best battery available. This is one time when the highest available cold cranking battery is the way to go.
Dear Doctor: I own a 2002 Chevrolet Impala. The “check engine” light comes on when it’s cold. The local garage has removed the gas tank four times for a sensor problem. They really cannot seem to find the problem. Any suggestions would be appreciated. Ann
Dear Ann: You need a technician who will research the trouble fault codes on both the Alldata and Identifix database systems.