June 14, 2007
Q. I have a 1995 Lincoln Continental with 85,000 miles. I had a tune-up done at 60,000 miles, and the only items replaced were the spark plugs. Just this past week, the engine has begun idling very rough when I come to a stop. It doesn't seem to matter whether the vehicle is cold or running at normal operating temperature. When I put the car in neutral, the idle becomes smooth. There are no “check engine” or “service engine soon” warning lights coming on. What do you think is wrong?
A. The very first item I would look for is a vacuum leak, which will cause a lean misfire. The engine will run smoothly on the road and in neutral. Possible sources of vacuum leaks are cracked or broken vacuum lines, leaking exhaust gas recirculation valve, or leaking intake manifold gasket.
Q. I’m in the market for a minivan and would prefer one with all-wheel drive. Which minivans with all-wheel drive have the highest safety ratings?
A. Currently, there is only one all-wheel-drive minivan on the market, the Toyota Sienna. The Sienna is rated by the National Highway Traffic Safety Administration as four stars out of five for protecting the driver and five stars out of five for side-impact protection. If all-wheel drive is a primary consideration, you might want to take a look at crossover SUVs such as the GMC Arcadia and the Chrysler Pacifica. Both offer seating for six, all-wheel drive and a five-star crash rating.
Q. I have a 1983 Ford F-350 pickup that pumps gas when it is cranking but will not pump gas after it starts. What can the problem be?
A. Check the wiring to the fuel pump. There is a diode in the fuel-pump relay circuit that can fail, causing the symptom you are experiencing.
Q. Friday I had to help my daughter move out of her apartment at school for the summer. Her college car, a 1992 Honda Accord, had "died" and she thought it needed a jump-start. During the move, I left the jumper cables connected from my car to hers because the car was “dead.” After 15 minutes, I tried to start my car but there was nothing. I tried starting it in neutral, thinking it might be the neutral safety switch -- nothing. I took a minute to just check everything out in the engine compartment. Noticing a fuse box that had a battery marker on it, I opened it and saw an 80 amp fuse for the battery appeared to be blown. Never have I heard of a battery fuse! I replaced the fuse and the car started. Should I be looking for something else?
A. The 80-ampere fuse is the main fuse for the electrical system, including the alternator. This fuse can fail due to many reasons -- although the most common way we see this fuse fail is during an improper (reversed) jump-start.
Q. I have a 1999 Jeep Grand Cherokee. Both brake lights are out but the little third brake light near the roof works fine. The bulbs are both good. Nighttime driving lights and directionals work fine. Any ideas why both main brake lights would go out at the same time?
A. There is a board on the back of the taillight socket. It is common for this board to warp from heat. When this happens, the brake lights will lose the ground side of the circuit and not light.
Q. My wife and I are moving to Florida and are looking to purchase an SUV down there in the next few weeks. We are deciding between the Honda CRV and the Hyundai Sante Fe. Both offer four-wheel-drive or all-wheel-drive options, and I am not sure which would be best. I want to get all the safety equipment that is necessary, since safety is my number one priority. I know all-wheel drive has great benefits for snow, off-road, and with towing, but these activities won’t apply to us. My main concern is heavy rain and wet roads. Will all-wheel drive increase our safety in the rain, or is the standard traction control on these SUVs enough? I do not want to get a feature that adds unnecessary expense.
A. All-wheel drive has advantages in all slippery weather conditions -- although in my opinion, the biggest safety advantage will come from stability control. Stability control will help overcome a skid by selectively applying the individual brakes. Both the CRV and the Sante Fe come with stability control and both have five-star crash test ratings from the National Highway Traffic Safety Administration. The Honda has great reliability and resale value. The Hyundai offers a great warranty, V-6 engine and more interior room. Both are good choices.
