Fuel pump may be too pooped to pump

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Q My granddaughter drives a 1995 four-cylinder Pontiac that runs well most of the time but sometimes will not start. To get it started you have to hit the fuel tank and the starter at the same time. While driving, the car will slow down to 10 mph for a while, then the engine will pick up again. The car's had a new head gasket and a good tuneup. The computers show no codes and it does not happen daily. Are there any service bulletins or recalls for these problems?

A Recalls on a 14-year-old vehicle? You are an optimist, aren't you? Since there are no fault codes and the ''check engine'' light hasn't come on, focus on the fuel pump, fuel pump relay and fuel pump circuit. Testing fuel pressure -- it should be 41 to 45 psi with the key on but the engine not running -- might confirm a fuel pump problem, but the fact that you have to thump the bottom of the fuel tank while cranking points to a high probability of a tired fuel pump.

Q My son has a 2002 Malibu with 110,000 miles. He has been having intermittent problems with his wipers and now with his signal lights. On three occasions he has had only high speed wipers. None of the lower or variable speeds work. Inadvertently he discovered that if he hits the washer button, the wipers work normally. Now for the second time his turn signals don't work. Last night I entered the signal problem into a Google search and got a suggestion to hit the emergency flasher button and then try the signals. Well, it worked. What's going on?

A I find that GM issued a ''special policy adjustment'' for inoperative turn signals/hazard flashers extending the warranty to 10 years/150,000 miles. I'd suggest checking with your Chevy dealer to see if this vehicle is specifically covered. In most cases, the ''fix'' is a new hazard warning switch.

Q I have a 1994 Saturn SL1 that I enjoy driving. The only problem is that the engine starts to heat up in traffic. The needle edges to hot, but when I turn on the air conditioning the needle drops to less than halfway. Is this problem related to the engine coolant temperature (ECT) sensor or some other sensor? I did change the thermostat, flush and refill the system before this change, which just started this summer.

A I'm not sure there's a problem. Your Saturn, like so many newer vehicles, employs an electric fan, rather than a mechanical belt-driven fan, to blow air through the radiator. This electrical fan will not come on unless the coolant operating temperature reaches about 220 degrees Fahrenheit or you engage the air-conditioning system.

In traffic, the vehicle isn't moving fast enough to generate adequate airflow through the radiator to keep coolant temperatures under control. If the coolant temperature climbs to that 220-degree threshold, the engine coolant temperature sensor signals the PCM (powertrain control module) to turn on the fan until coolant temperatures drop back into the 210-to-215-degree range. A scan tool may well identify a faulty ECT.

How high does the temperature needle go before you can't stand it and turn on the A/C? If it's only about midway between normal and hot, the coolant may not have reached that threshold yet. But if it continues to climb toward and eventually into the red and the fan fails to come on, there's a problem.

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