Auto Doc: Hard start after refueling
Dear Doctor: My 2003 Cadillac CTS starts and runs fine, however, when I refueled the past three to four times, I have to pump the gas pedal and it's hard to start. The car also runs rough the first few minutes. Any ideas? -- Frank
Dear Frank: The most common faults are inoperative evaporative parts in the system, along with vent and purge valves. I always look on or Identifix and Alldata to identify where the valves are located and the proper testing procedures. The driveability problem you are experiencing is from too much gasoline entering the engine causing a rich condition when the gas tank is filling and full. The charcoal canister may also now be damaged and full of gasoline, which will also need replacement. This issue can arise without setting the "check engine" light on.
Dear Doctor: I just bought a 2014 Nissan Frontier SL. Can I coat the brake lines and fittings, and nuts under the truck with anything to prevent rust? I was thinking of coating with grease or Vaseline. Those are petroleum products. Also, is there break-in oil for a new truck? I won't be driving much, so if I only have 2,000 miles the first year should I have the oil changed, or break the motor in with original oil? -- Jim
Dear Jim: You can use any good brand of rubberized spray undercoating (2 to 3 coats) to coat the lines and fittings that are a concern to you. Make sure you drive the truck weekly, making certain to get the engine up to temperature (warm). Some manufacturers do still use a break-in oil that supports engine wear-in. I would not go any more than a year before I remove the break-in oil. At my first oil change I would not use full-synthetic oil; wait until the mileage is at 5,000 miles. Rotate the tires yearly.
Dear Doctor: I own a 1999 Ford F-150 and the transmission slips. When I turn the "O/D" off the battery light comes on. The battery gauge stays normal, but the light comes on. What could be happening? -- Jorge
Dear Jorge: The first step is to check for transmission fault codes. Next is a check of all fuses followed by a check of all ground wires and connections at transmission connectors. If there are no codes and all connections are good, then the technician will need additional help from Identifix and follow the wiring diagram on Alldata. You could have two separate problems with this truck. It will take time to pinpoint each circuit.
Dear Doctor: I have a 2008 Honda CR-V with a four-cylinder engine, FWD, automatic transmission, which now has 72,000 miles. Periodically, when starting the car and the gear is in Park, the engine races very fast. It occurs when the engine has been running and I shift into park. The dealer tells me I'm doing it with my foot, but it races too fast for that to be the case. Your advice is appreciated. -- Vin
Dear Vin: Engine racing can be caused by many things, including sticking linkage if equipped, dirty throttle body plate, and air ports leading into the idle air control motor. Lazy idle air control motors or carbon in the air passageways and pintail will cause this issue, too. A weak battery can also cause the computer to get confused. You can have the technician disconnect the battery cables for 24 hours to erase all the computer memory and logic. This some times makes the difference, just as re-booting your home computer.
Dear Doctor: I'd like to buy a friend's 1997 BMW Z3. The car sits for months without being driven, and when it is driven it's only for short trips. Before I make the purchase and drive it 115 miles back to my home, what would you do to the car if you were buying it? -- Benny
Dear Benny: I see a lots of vehicles that are only driven in nice weather and some short trips. Most of these vehicles are driven when the temperature is 60-plus degrees, which in turn has the engine running at a warm normal temperature. The warm temperature will burn off any condensation in the crank case and exhaust. If the oil is clean, then yes, I would drive the car the 115 miles and then change the oil when you get home. Also make sure the tires are at the correct temperature, and coolant and washer fluid are full.
Junior Damato is an ASE-certified Master Technician. E-mail questions for publication to info@motormatters.biz. Mail questions to: Motor Matters, PO Box 3305, Wilmington, DE 19804
