Q: Dear Tom and Ray:

Knowing of your penchant for philosophical disputes between otherwise happily married couples, I thought I'd send you our disagreement. My wife and I live in Michigan, the state with two seasons: "Winter" and "Construction Season." We disagree on the best way to deal with the narrowing of a freeway by one lane due to construction. One of us, Spouse A (I'm not revealing which one of us it is, as I've noticed your definite bias toward wives), believes the proper way to approach these situations is to use all of the available road. Spouse A says drive right up to the orange barrels and then merge at the last moment. The other spouse believes that this behavior is inconsiderate, impolite and maybe even stupid. Spouse B thinks you should merge as soon as possible, even in heavy traffic. Obviously, we, and the rest of the nation, need your ruling on this matter.

-- Eric

A: TOM: Our vote goes to Spouse B, Eric. When you see a sign that says "Lane Closed 1/4 Mile," what that's saying is: "Hey, Bozo, you have a quarter-mile to safely change lanes. And if you don't merge within that quarter-mile, you're going to bash into our lovely orange barrels."

RAY: Most reasonable people understand what the sign means and immediately start signaling and looking for a safe opening. Then they safely merge, and they're all set. These people are known as "good citizens."

TOM: And then there are the Spouse A-types in their BMWs and Ford Explorers, talking on their cell phones, blasting past at 65 mph all the way up to the forced merge. And then they try to butt in front of everybody else. These people are known as "jerks." And, in our opinion, they are inconsiderate, impolite and maybe stupid.

RAY: You use the same rules as you would for a highway on-ramp. They give you a quarter of a mile to merge into traffic. But does that mean you're supposed to use the entire quarter-mile and then veer into traffic at the last second? No. You use as much of the quarter-mile as you need to make the merge safely.

Dear Tom and Ray:

My wife has an '85 Corvette with an engine that's racing. For about a year now, whenever she stops at a light it's been racing at between 1,100 rpm and 1,300 rpm. If she taps the accelerator pedal, it drops to 850 rpm. I took it to a mechanic, who said it was some type of air sensor valve, which he proceeded to replace. The problem continued. He then said it was the throttle body, which he also replaced. It still raced. Then, last week, he said it was the throttle cable, which he replaced. Now it's racing at 1,600 rpm! My wife is looking at me like I'm a chump, and I think I'm starting to agree with her. Before I take out a second mortgage to pay for more repairs (the throttle body was $500), can you give me some suggestions on how to proceed?

-- Jim

TOM: I'm going to start by suggesting you proceed to another mechanic, Jim. All of these things are reasonable guesses, but the fact that he guessed the cable last tells me that he's not approaching this very scientifically.

RAY: The first thing to do is to eliminate the cable from the equation, since--as you now know--it's a whole lot cheaper than a new throttle body. So you disconnect the throttle cable at the throttle body and see if the engine still races. If it does--with the cable disconnected--then you know the problem is in the engine compartment.

TOM: And once you narrow it down that far, then again, I'd continue by eliminating the simple stuff first. Rather than replace the air control valve and the entire throttle body, I'd check the throttle return spring. On a 15-year-old car, the return spring that closes the throttle could simply be worn out. And that could account for an intermittent fast idle.

RAY: And if the spring ends up fixing it, you're going to be awfully miffed at this mechanic. Why? Because the spring costs about 95 cents.

TOM: That may not be it. But I'd certainly eliminate that possibility before I spent any more money on parts. Good luck, Jim.

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