Q I have a 2001 Buick LeSabre I bought new. Recently, my grandson changed a broken serpentine belt. In the process, he found a pair of Vise-Grips [locking pliers] with pieces of rubber hose over each end pinching off the overflow hose just below the radiator cap. He removed the pliers and checked the coolant in the radiator. Instead of water, he found a creamy, tan-colored substance. I had the radiator flushed about three years ago by a shop that's now out of business. There was no mention of a leak or problem. Could this stuff be some additive they didn't tell me about? And what's with the Vise-Grips?

A The creamy-looking stuff is moisture condensed into the coolant. This occurs in cold weather because of frequent short trips or a faulty thermostat that doesn't allow the engine to come up to full operating temperature. What's with the Vise-Grips? I say a new addition to your grandson's toolbox -- I can't tell you how many tools in my box were found under the hood of cars I've owned.

The Vise-Grips were apparently used to disable the coolant recovery system by not allowing hot coolant from the radiator to expand into the recovery tank. Did this cause any harm? Probably not. Since there's evidence the engine didn't reach and maintain full operating temperature, the system likely didn't need to push coolant into the recovery tank.

I'd suggest having the cooling system completely flushed and refilled along with a new thermostat and radiator cap.

Q I own a '78 Silver Anniversary Corvette that's never been a good runner. My sister and I tried to take it out to a rally about 20 years ago but had to turn around and come back because it kept stalling on the interstate. Hot weather causes it to lose power and shut down. Then I flood it, and it won't restart for a while. I use premium gasoline. Sure would be fun to be able to drive it locally during the summer!

A Your "baby" is vapor-locking. Fuel is boiling in the fuel pump, fuel lines and/or carburetor. This starves the engine for fuel, causing rough running and stalling. You aren't flooding it; the percolating fuel floods it.

Some things you can try: Use nonoxygenated premium gasoline. No ethanol means it's less prone to "percolation." It's typically available for use in antique and collector vehicles. Have the cooling system completely flushed and refilled and make sure the fan clutch is operating properly. Also, make sure the radiator and air-conditioning condenser are clear of dead bugs and debris. Wrap the fuel line between the fuel pump and carburetor with a heat-resistant material. Install an electric "boost" fuel pump and switch to help overcome vapor lock. And carry a spray bottle of water to manually cool off the pump, lines and carburetor.

Q My wife has a Toyota Corolla that gets great fuel economy. I drive it occasionally, but the lack of legroom makes it uncomfortable to drive more than 15 to 20 minutes. I drive a roomy but aging Bonneville that gets 25 miles per gallon on my commute. When the Bonneville needs to be replaced, I'd like to get a Corolla because of the rising cost of gasoline. At the same time, I want to avoid the discomfort that comes from insufficient legroom. Is moving the seat a practical solution?

A Not really. It can be done, of course, but you'll have difficulty finding a shop to do this because of the potential liability. The broader issue: Can you find a comfortable car that delivers the kind of mileage the Corolla does?

The answer is yes. Sticking with the GM theme, the four-cylinder 2012 Chevy Malibu delivers 22 mpg in the city and 33 on the highway. The new Ford Fusion offers 23/33 mpg, and the 2012 Chrysler 200 gets 20/31. Plenty of legroom along with great fuel economy.