Q We have a 2008 Chevrolet Malibu with a four-cylinder engine and automatic transmission, and less than 35,000 miles. Two months ago, the intermediate steering shaft was replaced because of a noise under the car as I backed out of our driveway. A few days later, the steering wheel would turn quickly to the right and I would have to turn it quickly to the left before it would go back to center and steer properly down the road.
I took it back to the garage, and they said they could not find anything wrong, but they did adjust or reset a sensor or something like that. On the way home after leaving the garage, it did the same thing once again. Was there a recall for this problem?
A I believe your vehicle is fitted with electronic power steering rather than hydraulically boosted power steering. The system incorporates a steering position sensor, steering torque sensor, steering motor and power steering control module. In short, the two sensors monitor position, direction and amount of torque applied to turn the steering wheel and electronically command the steering motor to provide the appropriate amount of steering assist.
The first step in diagnosing any power steering problem would be GM's scan tool to check for fault codes relating to the electronic power steering. My Alldata automotive database pulled up a special service bulletin addressing a loss of power steering assist due to electrical issues in the steering column assembly. This bulletin, number 10183 and dated July 2010, extends coverage on this problem for a total of 10 years or 100,000 miles. On 2008 model year vehicles, the bulletin calls for replacement of the steering control module.
Q My 2001 Mercury Sable has the 24-valve, 3.0-liter engine and 93,000 miles on it. Recently, it has been stalling, usually after coming off a freeway. Upon accelerating, the engine just stops. There is no "check engine" light. Other times, when traveling only a few miles and then stopping for five to 10 minutes, the engine will not restart. It turns over just fine but does not fire.
I was told by a dealership that by rapidly depressing the accelerator one time and releasing it would restart the engine. That trick has worked twice out of more than a dozen events. The fuel pressure has been tested numerous times and is normal. When they hook up their electronic diagnostics, there are no fault codes reported. Can you help?
A To determine whether the stalling is due to lack of fuel or lack of spark, check the fuel pressure during an event when the engine won't restart. No fuel pressure might mean vapor lock boiling the fuel in the fuel rail because of high temperatures under the hood. Check for spark with a timing light or a spare spark plug. Vapor lock may be the problem.
Another possibility might be a sticky idle air control (IAC) motor. If this device, which regulates the amount of air entering the engine at idle, is not accurately doing its job, the engine may stall or not restart. Holding the throttle partway open might help a restart.
Q I intend to put snow tires on the front wheels of my Honda Civic and leave standard mud-and-snow-rated (M&S) tires on the rear for winter. However, the tire store said this was extremely dangerous and I should put four snows on, or leave the four M&S tires on. Their logic is that the front tires would grip but the back would slip. From my perspective I'd rather have two tires grip than have four that slip. Are they correct, or just trying to sell more tires?
A They are correct. Every car should have the same tires on all four wheels to ensure relatively equal traction on both ends. Four M&S tires will do well, but four winter tires will do better.