Dear Doctor: I own a 1998 Ford Ranger pickup truck with the V-6 engine that I recently purchased with 89,000 miles. The problem is a rough idle. I’ve had two mechanics check it. One repositioned the transmission lines and the other adjusted the engine mounts. The vibration is slightly better now, but I was told a vibration is normal on the both the V-6 and four-cylinder engines. Any suggestions would be appreciated. Ralph
Dear Ralph: I service many four- and six-cylinder Ford engines. I have yet to hear owner complaints about a vibration at idle. I recommend a number of checks you can do to determine the source of the vibration: Make sure the engine is idling at the correct speed; make sure the engine is running smoothly; check to see that the rubber-insulated engine mounts are in tact and that there is no metal-to-metal contact. I have seen the wrong size serpentine belt (too long) cause a vibration at idle. These are all things that need to be looked at to help eliminate the idle vibration.
Dear Doctor: I own a 2003 Toyota Corolla with 73,000 miles. My mechanic said it needed a new catalytic converter and he referred me back to the dealer because it is warranted 8-years/80,000 miles. The dealer said the front pipe was leaking which was causing the problem and it would not be covered under warranty. I went back to my mechanic and he looked at the front pipe and said there was no leak. I went to another shop for a smoke test and no leak was found. The dealer still insists the exhaust is leaking. What should I do? Jerry
Dear Jerry: My advice would be to try another dealer. If the treatment is the same, have your local mechanic make the repair using a factory catalytic converter and send the bill to Toyota and see if they will at least pay for the converter. Remember in the future there are a lot of very good brands on the market if you do not get any satisfaction from Toyota.
Dear Doctor: I purchased a 2001 Buick LeSabre with 52,000 miles. After driving it 2,000 miles the “check engine” light came on. The dealer said the problem was a faulty catalytic converter, not covered by the warranty. The cost of repair is $1,000. I went to another Buick dealer and they said it was a bad oxygen sensor. I had both the catalytic converter and oxygen sensor replaced. A couple of days later the service engine light came back on. How long can I drive the car with the service light on? What do you think the problem is? Sam
Dear Sam: Before we suggest any services, you have to use a factory GM replacement catalytic converter on this vehicle.