Dear Tom and Ray:

I've heard that you both graduated from MIT in Mechanical Engineering. If this is true, then we have that in common. But I hope we don't have my car problem in common. My car builds up a static charge. And as soon as I get out of the car and touch the frame, I get zapped. It's quite painful. I've tried wearing shoes with different soles, kicking the door shut, and now I just close the door by pushing on the window. However, the static charge remains in me, and the next thing I touch which is grounded zaps me. Some of my friends have suggested that my hair is too long, or that I have some sort of extra-chargeable seats. The most common comment I get is that I have an "electrifying personality." Short of shaving my head, what suggestions would you have to keep me from building up such a large static charge? -- Christine

Tom: We happened to solve a similar mystery about static electricity on our radio show a few years ago, Christine. A toll-taker called us, and told us that whenever a then-brand-new Honda Accord came by and the driver handed him a quarter, he'd get zapped! POW! So much so that he began ducking down in his booth whenever he saw a new Accord coming along.

Ray: It turned out that the new Accords were using a relatively new, "low rolling resistance" tire, which reduced rolling friction to improve gas mileage. And, you guessed it; static electricity leaves a car primarily through the tires. In changing the rubber compound to increase mileage, the tire maker had made the tire a poorer "grounder." So those new Accords were not dissipating static electricity as well as most of the other cars on the road.

Tom: And while the tire maker claims to have improved the grounding ability of that particular tire, the truth is that many tires are now "low rolling resistance" tires and probably don't dissipate static electricity as well as tires of old. It's one of the prices we're paying for better fuel economy. And my guess is that your tires are the crucial element in this equation, Christine.

Ray: Assuming that you're otherwise perfectly happy with your tires and your mileage, there are a couple of other things we can suggest. The simplest is to "discharge" yourself through something else. If you hold your metal car key, for instance, and touch IT against the grounded car, the charge will jump from the end of the key to the car, leaving your finger "unzapped."

Tom: But if you don't want to bother with it at all, most auto parts stores now sell "grounding strips" that hang from the frame of the car and touch along the ground. I've tried those and they work pretty well -- although since they scrape along the ground, they do wear out after several months and need to be replaced.

Ray: Of course, it's possible that the friction of the grounding strips will reduce your mileage by as much as the "low rolling resistance" tires increase it. But you'll have to figure that out, Christine. After all, you're the mechanical engineer. My brother graduated from MIT in Chemical Engineering.

Tom: And my brother graduated with a degree in Animal Husbandry, and even practiced for a few years ... until they caught him at it!

Changing your oil regularly is the cheapest insurance you can buy for your car, but how often should you change it? Find out by ordering Tom and Ray's pamphlet "Ten Ways You May Be Ruining Your Car Without Even Knowing It!" To order, send (check or money order) to Ruin, P.O. Box 536475, Orlando, FL 32853-6475. You can also order online.

© 1997 by Tom and Ray Magliozzi and Doug Berman Distributed by King Features Syndicate, Inc.

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