Q. I have an 2004 Audi A4 and lately I have noticed the RPM's are reading higher on the highway than normal. Also from time-to-time I notice a bucking. Are these problems related?
A. I think you will find the car is in need of a torque converter. With most cars today when the car shifts into higher gear ranges the torque converter puts the engine and transmission into lock-up (direct drive). At lower speeds the converter slips. I believe the torque converter in your car in not locking up. This is why you are seeing the higher than normal engine speeds. This can also cause the bucking sensation.
Q. I just recently purchased a 2006 Volkswagen Passat. Now that I've changed the oil, how do I reset the service reminder light?
A. Like many cars today, your Volkswagen requires a specialized scan tool to perform even simple tasks. To reset the oil change reminder light you will need to visit a Volkswagen dealer or independent Volkswagen specialist.
Q. I have a 2005 GMC Yukon. When I started the car in last several days, the speedometer reads at 40 miles per hour and sometimes 50 miles per hour. Do you why this is happening?
A. The instrument cluster on many of these GM trucks have had some problems. The repair will require removal of the cluster and having it sent out to be rebuilt.
Q. I own a 1997 Lexus ES300 with 184,000 miles. I feel a slight hesitation which is very pronounced when the car is coming up to highway speeds. At other speeds it is not as noticeable, but it is still there. I don't seem to feel it at all under hard acceleration. The feeling is akin to a slight lugging or misfire. I initially suspected a bad tank of gas or clogged injector and ran a bottle of fuel cleaner through it but there was no change.
I took it to the dealer and they said there were no error codes and could not replicate the problem. The car is drivable but I'm very concerned because I frequently drive out of state. What do you think could be causing this problem?
A. Have a technician look at the mass air flow sensor. This sensor can get dirty and sometimes they can be cleaned. The sensor isn't cheap, costing approximately $250 plus a minimal amount of labor to have it installed.
Q. With all that is going on with Cadillac and Lincoln these days I'm a little concerned about buying an American luxury car. One car that I thought I would never look at that has certainly caught my eye is the Genesis by Hyundai. What do you think of this car?
A. I recently spent a week in the Genesis (with the exception of the Hyundai logo on the trunk and wheels, the Hyundai name is not on the car) and found it to be very well constructed. The ride is firm but comfortable; the V-8 engine delivers plenty of power, while still returning nearly 25 miles per gallon on the highway. The overall fit and finish is "world" class.
The car that I drove had a suggested list price of $37,250 and easily compares to imports costing $10,000 more. Regarding Cadillac and Lincoln, I currently believe models such as the CTS and the MKS are some of the best models those companies have ever manufactured.
Q. I recently had my Toyota Avalon into the dealer to diagnose and repair an oil leak. The problem was a faulty oil supply line and the repair cost nearly $600. I purchased this car due to its reputation for reliability and now I am fast becoming disappointed. Did I get a lemon?
A. Like every other car, your Toyota can have problems. The problem with your Toyota has been addressed in a technical service bulletin (EG064-05) with an upgrade of the oil line. Toyota should have covered this repair under a 6-year or 60,000 mile powertrain warranty.
John Paul is the public affairs manager for AAA Southern New England. He can be reached at firstname.lastname@example.org.