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Larry Rubenstein

Q: I have a '96 Explorer XLT with all the bells and whistles. Every time I start up, I get a "check brake light" warning when I step on the brakes, and the same thing happens when I turn on the headlights. All the lights are working fine. I can push the reset button and the warnings go away.

No mechanic I talked to knows anything about this. The local Ford dealer tells me as long as the lights work, I have to just live with it. Is this Explorer haunted?

A: I don't think your Explorer is haunted at all. The brake light warning system works by checking resistance.

If you had a rear bulb changed recently, they may have installed the wrong bulb. If that isn't the case, you need to check the ground supply on all of the rear lights, including the third-eye brake light.

I will assume you have looked in the rear of the vehicle and made sure all three lights work. If all checks out well, then you will have to check the resistance in the wiring to find a possible frayed wire.

Sounds like a fun chore for a Sunday afternoon while listening to the Red Sox do their thing.

Q: I have an interesting condition on my 6-cylinder 2000 Camry that happens sometimes after the engine is warm. It feels to me like occasional engine misfires. I can feel it when driving on a level road at around 40 mph, that is, when I'm neither coasting nor accelerating, but just giving it a little gas to maintain speed. It feels like I'm hitting little bumps in the road every few seconds. If I give it more gas, the problem goes away. When stopped and idling, I can hear and feel that the engine "misses a beat" from time to time.

The problem has been coming and going for a couple of years. One time I got a check engine light, but it went away. I took it to the shop and they said there were no stored codes, and of course it didn't misbehave when they drove it. They cleaned the throttle body and the car behaved for a while, but it does that on its own anyway, so I was never sure whether the improvement was related to the action taken. What do you think?

A: Your car has a computer system called "OBD II." A beautiful part of OBD II is a process called Mode 6. Mode 6 shows pending problems that are present but haven't turned on a check engine light yet.

More than likely you have a spark plug with a hairline crack, an external vacuum leak, or even an intake manifold gasket leak. Using a scanner, the short-term fuel trim numbers will confirm the probability of an intake gasket leak.

Car Care Tip: Driving around with a leaking radiator can very quickly cost you a replacement motor. If you can't afford to fix it now, park it until you can do so.