Dear Doctor: I have a 2002 Nissan Sentra with 135,000 miles. Recently, when slowing down the engine stalls. After stalling the "check engine" light comes on. Every other aspect, such as idling and acceleration, are fine. I tried additives to the gas. Can you help? -- Jim
Dear Jim: The first step is to check that the computer communicates with the scan tool and check for any codes or pending codes. Next, try an idle motor relearn. This will require a scan tool. Carbon buildup in the throttle body is also a factor. I looked on Identifix and also found additional possibilities: poor ground connection under the battery and right side of the valve cover, as well as throttle position sensor failure.
Dear Doctor: I own a 2000 Honda Accord four-cylinder with 125,000 miles. The "check engine" light came on, so I had the computer scanned and it showed all cylinder misfires and code 1399. I had a full engine tune-up and distributor replacement, but the same codes still come back. Do you have any ideas? -- Steve
Dear Steve: I have found that the exhaust valve seat in the cylinder head wears down, allowing the valve to sit closer to the rocker arm, causing the valve not to close fully. We have also found tight exhaust valves, which can cause a slight engine skip and rougher than normal idle. In some rare cases, a loose timing belt can also be the culprit. We see the problem you describe often after a shop or owner has replaced all related tune-up parts. At my shop we use Identifix and Alldata. They advise us to adjust the engine valves on both the four-cylinder and V-6 engines at 100,000 miles.
Dear Doctor: I have a 2011 Audi A6. My wife thinks that the passenger side seat is very uncomfortable. Do all European cars have very firm stiff seats? I was thinking about purchasing an aftermarket seat cover or cushion. Would you have any recommendations? -- Steve
Dear Steve: The seat foam can be trimmed or replaced with a softer foam. This is not a major undertaking to take the seat cushion apart. The seat position where the seat frame mounts to the floor can also be shimmed. You need to check with an upholstery shop in your area. As for seat covers and cushions, I suspect the support would not be enough.
Dear Doctor: I own a 2010 Chevy Equinox. The rear defroster and sideview heated mirrors have stopped working. Three times back to the dealership for repairs, but within 24 to 48 hours they have stopped again. How do we fix it? -- Roger
Dear Roger: Input commands go through the Body Control Module. The BCM should have trouble fault codes stored in memory, though a "check engine" light might not go on. Identifix has a step-by-step trouble shooting procedure listed. With the key in the "on" position, there should be battery voltage at the fuse in question. You will need to speak with the dealer technician and ask exactly what they did for the service repair that made the fix last only a day or so.
Dear Doctor: I'm thinking about getting a new car and would like to know if you have driven the Volvo S60. -- Pat
Dear Pat: I drove the 2014 Volvo S60 T6R AWD. Powering our tester was the 3.0-liter turbocharged 6-cylinder making 325 horsepower (up 25 hp over the standard S60 T6). There's almost no turbo lag from a start. And power goes to all four wheels, making for super fast starts from a stop. The ride was forgiving over broken pavement. Volvo has always been a safety leader and just one example is the bright cornering lights that come on automatically when turning in either direction and illuminate everything in eyesight. -- Junior Damato, Motor Matters
Junior Damato is an ASE-certified Master Technician. Email questions to email@example.com. Mail questions to: Motor Matters, PO Box 3305, Wilmington, DE 19804