We are a happy one-car family but need to expand to two vehicles for a short while so I can do data collection toward my Ph.D. dissertation. I think I’ll need a vehicle for about a year, and then I’d be ready to let it go again. What’s the most affordable way to do this? I need something that’s reliable for winter travel, and I don’t mind having a payment for the short term. I just hate to get a three-year lease when I need a car for only 12 months. Of course, I will have a committee ... so maybe I’ll need three years after all.

Judging from how long it took my brother to finish his dissertation, I think you might need one of those 84-month leases. Maybe two of them. Actually, I have several options for you. The time-honored option is to borrow a car from a relative. But if that’s not in the cards, the best solution is a late-model used car. Cars that are 3 to 5 years old tend to still be very reliable these days (assuming they’ve been checked out and OK’d by your own mechanic).

Because depreciation has already taken a huge bite out of the value of the car during its first few years, cars that are 3, 4 and 5 years old tend to be good deals: You’ll probably pay less than half of what the car originally cost. And because depreciation slows down as the car gets older, you’ll lose less when you sell it.

So, let’s say you buy a 4-year-old Subaru Impreza, just as an example (with all-wheel drive for the winter). And let’s say you find one with less than 60,000 miles for $12,000. If you don’t beat it up too badly (if your data collection doesn’t involve chasing polar bears around glaciers), you might be able to sell it a year later with 75,000 miles for $9,000 or $10,000. So that’s the general approach I’d recommend.

A second option depends on the age and condition of your current car. If it’s older and will need to be replaced in the next couple of years, you might consider buying a new or newer car as the “family car.” You would use your existing car for a year to do your data collection. Then you’d sell the older car and keep the newer one as the family car when you finish your dissertation — or in 2027, whichever comes first.

Good luck. Send us a copy of your tome when you’re done. Like your friends and colleagues, we won’t read it either, but I’m sure we’ll be impressed by its heft.

I have a ’69 VW Bug. When it’s just sitting still and idling, it runs great. But when I let out the clutch, it takes off fine, then bogs down to idle speed, then it takes off again and bogs down again. It does this continuously. I have replaced the points, the condenser, the rotor and distributor cap, and the plug wires. I’ve also rebuilt the carburetor. What do I try next?

How about a ’79 Rabbit?

Let’s assume you gapped the points correctly and set the timing correctly. In that case, the next thing I’d do is pull out the spark plugs. If they’re all black, it means you’re getting either way too much fuel or insufficient spark.

So if they’re black, I’d replace the coil for $25. I’d also re-gap the spark plugs, because misgapped plugs also could cause weak spark.

If the plugs are clean, then I’d turn my focus to the carburetor’s high-speed jet. And yes, I’m aware that the term “high-speed jet” is an oxymoron when talking about a ’69 Bug, but that’s what they call it. Even though you say you’ve rebuilt the carburetor, the high-speed jet may still be plugged up.

When you first step on the gas pedal, you deploy something called the “accelerator pump.” That’s sort of like a little water pistol that shoots a stream of gasoline into the throat of the carburetor. It lasts only a few seconds, but it allows you to accelerate while waiting for the carburetor’s high-speed circuit to kick in and provide continuous fuel.

But if the high-speed jet is plugged, after a few seconds of acceleration you’ll run out of the fuel provided by the accelerator pump, and the engine will fall back to idle speed. That’s why you surge ahead, and then bog down, surge ahead, bog down, ad infinitum.

But rather than rebuild the carburetor again, I’m going to suggest that you just buy a new one. It’s not because I lack faith in your carburetor-rebuilding skills, I lack faith in everyone’s carburetor-rebuilding skills.

New carburetors for this car are still available, and you can get one for less than 100 bucks. So why not? Put one in, and I think you’ll be right back to doing those five-minute 0-to-60-mph runs.

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