Drive it forever; Don’t get your wires crossed

Dear Mike: On my car radio’s installation instructions, it shows only one red wire (hot) going to the positive side of the battery. How do I complete the circuit without a ground wire? I am installing it in a boat.

A: You’ll need to run a ground wire to the metal case of the radio. Car radios are normally grounded by their mounting hardware. Actually, the shield wire on the antenna will also provide a ground path. Of course cars and trucks have metal bodies to conduct the current. Boats do not, so you simply need to run a wire.

Dear Mike: I own a 2000 Chevrolet Tracker with a 2.0-liter engine that has a noise coming from the timing-chain area. My dealer says that the repair will cost $1,200, mostly due to labor. How do you correctly diagnose this problem, and can a guy with average mechanical ability do the job himself?

A: The dealer is giving an estimate for a worst-case scenario, which the law requires. He can’t legally raise his estimate after he gets into the engine. If it hasn’t damaged more stuff, a timing chain and tensioner replacement should be pretty straightforward. If you’ve got the tools, give it a go. You may be able to simply change the tensioner. Be sure to get a good shop manual, though.

Dear Mike: We have a 2006 Kia Sedona that we like…when it starts. We have taken it into the shop twice. The first time they fixed the transmission cable, and then two days later we had to have it towed to the shop for the same problem. It lasted three months, but now it’s starting to have the problem again. The car won’t start because the gear shift won’t put the car in park or neutral, and the indicator on the console shows the transmission in a different gear than it’s actually in.

Do you know if this is a problem with all Kia Sedonas, or am I simply a lucky owner? My vehicle has 22,000 miles on it.

A: Our Sedona long-termer didn’t have a problem. Have they replaced the cable or are they merely adjusting it?

Dear Mike: I have been looking for a confirmation of whether or not acetone mixed with gasoline will improve gas mileage.

I read on the Internet that 10 gallons of gas mixed with 2 ounces of acetone would improve mileage without damaging the rubber in the vehicle.

A: Urban legend. Don’t do it.

Dear Mike: Is there a way to wire the headlamps so that they come on when the ignition is started?

A: Yes. Move the lead from the headlight fuse to one that is hot only when the key is on. And remember to leave the headlamp switch on all the time.

Dear Mike: I have a question about hybrids that it seems no one has addressed, to my knowledge.

The concept that the Prius and Highlander use to recharge their batteries through friction from the brakes is genius. My question is: could this same concept be used for a clutch, seeing as there is so much friction there? It would be great if a hybrid was made with a standard transmission, because I don’t know if I can ever go back to an automatic transmission.

A: The recapture of energy in hybrids does not rely on friction. Consequently there is no way to capture the friction in the clutch. The Honda hybrid uses a manual transmission.

Dear Mike: My husband received his June 2007 issue of Popular Mechanics, and we were both shocked by the article in the car-clinic section showing the “correct” technique for siphoning gas — using a thin piece of hose and a compressor to blow air into the tank, forcing fuel up the hose.

What has happened to common sense? Have you been a victim of stolen gas?

A: I’m thinking that any crook who already has your car in his garage next to his air compressor has already stolen the entire car, and won’t need to siphon the gas. Not to mention that most cars have gas caps with interior releases, and can’t be opened without access to the car.