Q. I am writing on behalf of my boss. He is very elderly with many physical health problems (i.e., fractures, bad back, walks with a cane). He lives in the suburbs, and drives in the city. He says that his car, a 2006 Cadillac DeVille, is uncomfortable and aggravates his aches and pains. He has had his car checked out, and we have put pillows in the car to make it more comfortable, but that hasn’t eased his discomfort. He wanted me to find the Car Doctor to ask which cars are best when it comes to smooth ride and comfort.

A. Certainly some cars offer more comfort than others, especially as we get older. Cars with European-designed suspension systems handle well, but can ride very firmly. Seats that are designed with deep bolstering that are great at holding their occupants in place can be difficult to get in and out of. Three vehicles worth looking at for a smooth ride and comfortable seating are Lexus ES350, Volvo S80, and Ford Taurus. Unfortunately, it is hard to know which car would be best. Considering this specific situation, I would consider renting a car for a week or so before buying it to ensure you made the right decision.

Ram doesn’t want to run

Q. I have a 1999 Dodge 2500 Ram van with 85,000 miles on it. When I start the car from hot or cold, and I am idling or I have just started driving, it seems that the car is starving for fuel. I can hear it sucking air, and it backfires through the intake. But if I shut off the key and restart the car, the problem disappears immediately. The van will run perfect after that, not missing a beat. If I don’t shut off the car, it will not straighten out and doesn’t run right for a long time. I have replaced the three sensors around the throttle body and did a complete tune-up with no improvement whatsoever. It has been doing this for a long time, 6, 000 miles, and has not changed a bit. Nobody can resolve this issue. It does not do this every time I start the car, maybe 6 times out of 10.

A. Something to look at is the wiring for the heated oxygen sensor. It is possible the oxygen sensor is picking up voltage from the heater circuit. If this happens it will affect the running, causing exactly these symptoms. A technician with a lab scope should be able to verify the problem.

Fill-up a 20-minute affair

Q. In the past few months I have been having trouble filling the tank on my Toyota Highlander. Sometimes it takes me as long as 20 minutes to fill up the tank. My repair shop thought it was going to need a filler hose. I spent $250 and still have the problem. What is wrong?

A. Have the garage look at the evaporative emission canister, and check valve and vent hoses. Although I haven’t seen the problem specifically with the Highlander, I have seen a similar situation with the Sienna minivan, and it was due to a spider nest clogging the vent hose.

Aurora light phenomenon

Q. My 1999 Oldsmobile Aurora has a headlight problem. Every few minutes the headlights blink on and off. Eventually this kills the battery. What do you think is wrong?

A. The problem is most likely a faulty headlight switch. The switch over time can develop enough resistance to turn the headlight lamp module on and off.

If it sputters, smokes or stalls, John Paul, the AAA Car Doctor{+s}{+m}, has the diagnosis. For an archive of his past prescriptions for car ailments go to: www.projocars.com

projocars@projo.com