Dear Tom and Ray:

I have a 1993 Mitsubishi Eclipse, and about two months ago I noticed a ticking noise coming from underneath the hood. I took it in to a mechanic, and he said my valve lifters were going out and I needed to replace them. I didn't have the $500, so I haven't done it yet. However, two weeks ago I noticed that the noise has disappeared. Does that mean my lifters have gone out completely? Is my car going to die on me? How much longer do I have? -- Rossanna

TOM: Only your doctor can tell you how much longer you have, Rossanna. But your car is just fine.

RAY: My guess is that one of two things was causing the ticking noise. It could have been a valve lifter. The valve lifters are responsible for keeping the valves properly adjusted by taking up the slack in the valve train. And they work by getting filled up with oil, which is under pressure from the oil pump.

TOM: So it's possible that one or more of your lifters was not getting filled with enough oil. And when they're not working, what you hear is the clicking and clacking of the valves. Why they eventually got filled up with oil again, I don't know. Maybe there was a piece of debris in the way that finally got dislodged. But in any case, they're now working again, and all's right with the world.

RAY: The more likely possibility, in my opinion, is that one of your valves got stuck. That would also cause a tapping noise that would be indistinguishable from the noise of a faulty valve lifter. And a stuck valve can get "unstuck" by itself, too.

TOM: And in either case, your car is fine and there's nothing you need to do. As long as it's not making any noise now, I would forget about it entirely. Just change your oil and filter every 5,000 miles or so, and forget you ever wrote to us, Rossanna.