Q. I bought a used Nissan Pathfinder about two years ago. I have already had two starters replaced and now I find out my Nissan needs wheel bearings in the front. Should I think about trading this in and if I replace it, have you driven the newest Pathfinder?
A. Certainly it is frustrating to have to pay for ongoing repairs for the same problem. The second starter could have been a result of a poor quality rebuilt unit. I would be only concerned if the second starter turns into a third. The wheel bearings repair may not be unusual depending on the mileage and how the vehicle was used. At this point I would have an overall inspection preformed on the vehicle. A good technician should be able to give you an overall “bill-of-health” rating to help you make a decision on keeping your Nissan. I have just driven the newest Pathfinder and found it to be one of the best vehicles in its class. Ride, handling and comfort were all very good. Fuel economy certainly could have been better, with my test drive averaging about 18.5 miles per gallon.
Q. I have a 1999 Chevy Tahoe that is setting a P0305 code. I replaced the cap, rotor, fuel filter, plugs & wires. Now it seems as if I have no compression in Cylinder 5. It is running very rough and sounds like an idling Harley and rumbles like one as well. When driving above 50-55 miles per hour it rides fine. Below that speed it jerks uncontrollably, begins to hesitate, then stalls. What could it be? Help; do I need a valve job or due to the age of the vehicle would it be best to just swap the engine?
A. If you have no compression in cylinder 5, you either have a burned valve or completely worn rings. A compression test will help. Add oil to the number 5 cylinder, if the compression goes up, it is a ring problem, if not you have a valve problem. You could also do a cylinder leak-down test. In this test air is injected into the cylinder, listening to where the air is leaking out will determine what is wrong. Regarding an engine swap, if the body and other mechanicals are in good shape, this type of repair might make financial sense.
Q. Concerning your article "Synthetic Oil" in the paper, you talked about the advantages of using synthetic oil. I agree 100 percent with you on the "advantages", but what about the "disadvantages" (if there are any)? When in your opinion is it a waste of money to change from mineral oil to this synthetic oil? I have a family member that thinks you can switch at anytime, even when the engine (not "motor" as some people continue to call it) has 100,000 or more miles. I appreciate your professional opinion on this matter.
A. The biggest disadvantage to using synthetic oil is it tends to have high detergent qualities and may cause an engine with a minor oil leak to get worse. Synthetic oil will not cause a leak but if the engine has a fair amount of sludge, the detergent will wash away that sludge and make a minor leak more apparent. If your car’s engine burns oil, using synthetic oil that has a retail price of up to eight dollars a quart may not be money well spent.
Q. I have a 2002 Volvo S60 AWD, a great car with a bothersome problem. The clock will intermittently run wild, sometimes at start up and randomly at other times, usually stopping after a few minutes. The trip odometer also intermittently resets to zero sometimes when the clock begins to run wild and at other times on its own. My mechanic called a Volvo dealer who never heard of the problem. Any suggestions?
A. It sounds like it could be a failure with central electronic module (CEM). This module controls many items within the car. The Volvo dealer will perform some testing to see if there is a software update to this module.