I have a 1979 Jeep CJ-7 with a 5-liter V-8 engine. The ignition switch is the type commonly used in vehicles of this vintage, and it's located on the steering column. It has an "accessory-only" position; an ignition-on, "run" position; and a spring-loaded, "crank" position, which activates the starter motor as long as you hold the key there. When I go to start the engine, I turn the ignition switch to the "crank" position, and the starter motor cranks normally. But the engine will not start until after I release the key and it springs back to the ignition-on, "run" position. I wired a remote starter switch directly into the starter solenoid and tried starting the car with that. And as long as the ignition switch was in the "run" position, I could make the starter motor crank and the engine fire up normally while the starter motor was still turning. Any ideas?

RAY: We were just trying to remember the last time we saw a '79 CJ-7 in the shop.

TOM: We couldn't remember, so we also took a moment to thank the automotive deities for that small blessing.

RAY: The first thing I'd suspect and test would be a bad ignition switch in the steering column.

TOM: What you want to do is test that "crank" position. When the key is in the crank position, both the starter motor and the coil are supposed to get power.

RAY: The starter motor, obviously, gets power to crank the engine and get it turning. And the coil gets power to fire the spark plugs, so that once the engine starts turning, it will "catch" and keep running on its own. You're obviously getting juice to the starter motor in the "crank" position, but maybe not to the coil.

TOM: You can find out with a test light. You obviously have some basic skills, since you hooked up a remote starter without setting your car on fire ... yet. So hook up the light between the negative terminal of the battery and the positive (ignition) side of the coil. Then turn the key to "crank." My guess is that nothing will light up.

RAY: That suggests that the ignition switch is bad. So your next step would be to try a new switch. But, as you know and undoubtedly toss and turn at night thinking about, changing the ignition switch in the CJ-7 is a pain in the rear differential.

TOM: So try a new switch without installing it first. You should be able to reach under the steering column, unplug the wires that go into the existing switch and then plug those wires into your new switch, which you'll leave dangling from the wires for now.

RAY: Then use a screwdriver to turn the new switch and see what happens. If it works, you can then remove the steering wheel and all that, and install the new switch permanently.

TOM: Or just leave it dangling. I think that's a nice touch on a '79 CJ. Good luck.

I've got a question that arises from time to time in my office. Oftentimes, we need to visit faraway cities and towns within the state for meetings and the like (and long lunches). They give us two options: We can get a per-mile reimbursement if we use our own car, or we can rent a car. I know that the reimbursement allowance is to cover wear and tear as well as gas, so how do I value said wear and tear?

RAY: I would always rent a car.

TOM: Sure. Most companies, and the federal government, will reimburse mileage at 55 or 60 cents a mile. That's supposed to cover gas, as well as wear and tear on your car.

RAY: But trust me, you're not going to make money on that deal. At best, you'll break even. Every year, the IRS calculates the average cost of owning, maintaining and repairing a car, and divides that by the average number of miles driven to get the mileage reimbursement.

TOM: And sure, it's nice to get that reimbursement check now, because it's always more than you spent on the gas - so it seems like a windfall. But that's money you will need for future repairs, and you're essentially borrowing from the future of your car.

RAY: Plus, there's some wear and tear that's just not calculable. What if Selma the slob from sales spills her venti skim latte on your front seat? What's the mileage reimbursement for a big, brown stain and sour-milk odor?

TOM: Or what if 350-pound Bruno from marketing yanks off the door handle because he's an animal?

RAY: Or what if you have an accident? Sure, you probably have insurance to cover the cost, but what about the deductible and the inconvenience?

TOM: Whereas if you use a rental car, I can guarantee that there will be absolutely no wear and tear on your car. Plus, you get to drive a reliable, new car that your kids haven't turned into a rolling junk pit yet. That's how I'd roll.

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