Drive it forever
Q. I've driven my 2004 Camry only 1,500 miles in four months. I use Pennzoil synthetic oil.
Is this a good brand of synthetic? Should I be changing the oil at a time interval, rather than at 3,000 miles? Will the oil hold up for six to eight months without being changed? Once a week I take the car out on the highway for about a half hour and run the A/C.
A. Yes to all three questions. And taking that half-hour weekly ride is the best thing you can do for this car.
Q. How do I remove the valve cover on the driver's side of my 1996 Chevrolet pickup truck with a 5.7-liter engine?
A. From the shop manual: "Disconnect the battery-negative cable assembly from the battery's negative terminal. Remove the spark-plug wires. Disconnect the wiring harness from the clips and move aside. Remove the following components for access to the right-valve rocker-arm cover: the crankcase-vent hose, the oil-level indicator tube bracket and the air-cleaner intake duct.
"Remove the following components for access to the left-valve rocker-arm cover: the air-conditioning compressor and lay aside (refer to 'Heating and Air Conditioning'), the EGR-valve inlet pipe, the PCV and the hose, and the power-brake vacuum pipe, and move aside.
"Remove the valve rocker-arm cover bolts. Remove the valve rocker-arm cover and the gasket.
"Clean all traces of old gasket from the valve rocker-arm cover and the cylinder head.
"Inspect the valve rocker-arm-cover sealing surface for distortion. Replace the valve rocker-arm cover if necessary."
Q. There is a guy running around this area with a white Saleen Mustang that looks like it was a Popular Mechanics project car from the late 1980s or early 1990s. I think that your magazine raced it in the Sports Car Club of America solo 1 or 2 class.
I have pictures of the car, and want to show them off on a Mustang forum, but wanted more information on the car
Can you offer any information on it?
A. That's probably the car we raced back in the early 1990s in SCCA and International Motor Sports Association professional endurance races. I crashed it at the Mosport International Raceway.
When we folded up our racing team, the car was acquired by one of the mechanics. I've lost touch with him over the years, but he lived near Akron at the time. It may have changed hands.
Q. My wife's 1996 T-bird - with a 3.0L V-6 - has a little under 70,000 miles on it.
She has been complaining lately about it pinging or knocking, especially going up the hills in our area, so I suggested that she use regular-grade gas and take it out of overdrive when she climbs the hills. These helped, but it still tends to ping.
Then recently the "check engine" light came on. I received an OBDII tester for Christmas, so I plugged it in and it gives me a code: "P0174 system too lean, bank 2." What checks would you recommend I perform?
A. Replacing the plugs almost certainly won't help. On the other hand, if the original plugs are still in there and I were doing it myself for cheap, I'd replace them.
If the mixture is too lean, the computer will richen up at least a little, so a bad O2 sensor can give you weird symptoms. A misfire in one cylinder will let unburned oxygen into the exhaust. The sensor will see the extra O2 and richen up.
Something is driving that bank lean, and it could be dirty injectors, a lazy O2 sensor, a vacuum leak or maybe even an exhaust leak. It could be a malfunctioning or plugged EGR system, or any of a dozen other things.
Mike Allen is a senior editor for Popular Mechanics magazine. Questions should be sent via e-mail to driveit@nytimes.com.
