Dear Jim,

I have a 1993 Honda Civic DX (1.6L, L4) with around 200,000 miles on it, but it's been running beautifully.

Several days ago, the engine started misfiring every 10 seconds or so. At the service station, they decided it was a computer problem and replaced the computer the next day, but the problem was back by the time I got home.

Another repair shop checked everything and said it was in the electrical system, so they replaced the distributor cap. Now the engine is still misfiring and even stalling out sometimes, and I'm very frustrated.

Any idea what I should do here?

-- Anish Gupta

All right, bro, assuming the fuel pressure has already been checked, I'm guessing you have a bad igniter. This tends to happen with a lot of early '90s Hondas, and if that's what's going on with your Civic, it would definitely cause the trouble you're describing.

If the engine is misfiring, then yes, that's an electrical problem. The sparkplugs receive current through the plug wires, which are connected to the distributor cap. The cap, in turn, gets its juice from the distributor rotor, which is fed by the igniter.

I'm frustrated along with you, and a little outraged, too.

That computer replacement was an expensive, extreme repair. The shop that replaced your distributor cap was closer to the answer, but they could have taken a few seconds to test the old one to make sure it was really broken -- it's just a plastic part with metal contacts, and it's very easy to check.

The igniter is a more complicated electronic component that makes or breaks a connection, and you can't directly diagnose it with nearly as much ease.

But if all those other parts (plugs, plug wires, distributor cap and rotor) check out OK, then the igniter is the culprit here.

Take your car back to that second place and ask them to change it. I'm betting a new igniter will take care of the misfiring problem completely and end your frustration.

Talk to the guys at the first shop, too. Chances are, you had a perfectly good computer replaced for no reason.

Tip of the Week:

A lot of people are asking about fuel economy these days, so here's a little laundry list of things you can do to maximize yours:

Keep tires inflated, replace dirty air filters, worn sparkplugs and oxygen sensors, change oil regularly and make sure your gas cap is tight. Doing none of these things can cost you up to 12 miles per gallon.

Buffalo Jim, owner of Allstate Auto & Marine Repair in Las Vegas, writes a weekly column. Send your automotive questions to him at buffalojim@lasvegasniftynickel.com. If Jim picks your question to answer in Nuts & Bolts, you'll also be the proud recipient of a deck of official Buffalo Jim playing cards, presented in a classy, tin box bearing his hairy image.