Q. My car’s heater gauge only goes up two lines, when in the past it would go up at least half-way on the gauge. What could be the problem?
A. The very first place to start looking is engine temperature. The engine temperature is controlled by the thermostat in the cooling system. If the thermostat is opening prematurely, the engine will not get up to operating temperature. Replacing the thermostat should solve the problem. At the same time the garage may recommend flushing out the cooling system. This will wash away any rust or scale that is in the radiator and engine.
Q. I own a 2002 Buick LeSabre Limited. I recently noticed that the oil pressure gauge is now reading 25 at idle and 45 or so while driving. It normally reads in the 50-65 range. The car has 99,000 miles. Is it the gauge or is this a sign of a more serious problem?
A. The specification calls for 60 pounds of oil pressure at 1850 engine rpm-using 10w-30 oil. If the pressure is less than this it could be the result of a worn oil pump, engine wear, faulty oil sender-switch or even low oil. The first thing you should do is check the oil level and the condition of the oil itself. If the oil is diluted it will cause the oil pressure to fluctuate. If the oil looks good, most technicians will remove the factory switch and install a mechanical gauge to measure the actual oil pressure. If the oil pressure still reads normal they will replace the oil-pressure-sending unit. If the oil pressure still reads low then they will look for other problems.
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