Why is my car so sluggish on the hills?

Dear Car Talk

Dear Car Talk | Nov 01, 2003

Dear Tom and Ray:

My company recently moved, and I now have to drive a hilly highway every day. The drive is pleasant (no traffic), but my 1990 Honda Civic has a very hard time with the hills. I find I have to downshift to get up every hill, and I can't go over 50 mph. Everyone passes me like I'm standing still (except for the big trucks, which share the right lane with me). Surely some of these cars that whiz by are older, like mine. What would cause my car to be so sluggish on hills? -- Maureen

RAY: Well, I think you're OK for the moment, Maureen. But when you see the garbage trucks start to pass you, and the guys hanging off the back are waving to you as they fade into the distance, then it's time to take action.

TOM: Actually, it's worth having it looked at now, Maureen. Unless these are extraordinarily steep hills, a Honda Civic ought to be able to negotiate them at the same speed as other traffic.

RAY: On a car this age, there's a long list of potential causes for your problem. But you want to check the most serious things first.

TOM: Start with a compression test. If you have low compression in one or more cylinders, that'll tell you that your engine is plum worn out. That would be bad news for this little Civic. If that's the case, you have a limited number of choices.

RAY: You can put a used or rebuilt engine in it, if the rest of the car is still in good shape. You can just drive it, at least until it gets a lot worse. Or you can take it out behind the garage, put a bullet behind its side-view mirror and start looking at the new Acuras.

TOM: If the compression is good, then another thing to check is the clutch. If your clutch were slipping, you would hear the engine revving up as you step on the gas, but the car wouldn't seem to go any faster. That's hundreds of dollars, but at least it's not thousands. And that's definitely worth fixing.

RAY: There are lots of other possibilities, too, Maureen. Anything that's wrong with the engine will be most obvious when you try to drive up hills at a high speed. That's when you're asking the engine to work its hardest. So, even relatively minor stuff, like incorrect timing, or a clogged fuel injector, fuel filter or air filter, could be at fault here.

TOM: But if the compression is OK, the problem is solvable. And if the compression is bad, you can keep driving it as long as you can stand it. And think of the good you're doing for society at large -- passing you going up hills is giving those garbagemen something to look forward to every morning.

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