Q: I wanted to change the spark plugs on my motorcycle. It looked like an easy job, compared to the struggle I had changing the plugs on my wife's car.
Access to the plugs was pretty easy, but the plug connectors wouldn't let go. I broke both connectors trying to free them.
Naturally the auto-parts department didn't have the right components, so I had to order a full set from the dealer for way too much money.
A: Your problem isn't one of metal-to-metal adhesion caused by corrosion or heat. It's probably simply the rubber dust boot on the plug connector acquiring an affinity for the plug's ceramic body, caused by years of close contact and countless heating/cooling cycles. And, trust me, cars have the same issue. I actually own a set of pliers with curved, cushioned jaws meant for teasing a spark-plug connector away from its home.
Try rotating the plug connector until it breaks loose before trying to pull it off. And in the future add a generous dollop of silicone dielectric grease inside the spark-plug connectors. This will not only keep the boots from sticking to the plug, but also provide a nice barrier against water and contaminants.
If you had gone to a dedicated auto-parts store, incidentally, the counterman could have hooked you up with a couple of connectors to replace your broken ones, for far less money than you paid for the full plug-wire set.
Q: Regarding your response to the question about changing the brake fluid every 30,000 miles, my question is this: Is there any harm if this scheduled maintenance is not performed? I take it that your braking performance may lessen, but will it do any harm to any hardware in the car?
A: Eventually the absorbed water and abrasive-wear particles in the old fluid will corrode the steel brake lines and wear out the rubber seals. But it will take a long time.
Q: I have a 1998
There are no blown fuses in the car and the relay is working fine. What could be wrong?
A: How much are you drawing from that outlet? It is probably only fused for 10 amperes, which isn't much when you're powering audio equipment. Ten amps at 12 volts will equal only 120 watts.
Check the name plate on the amplifier and see what it draws. You may need to power your gear from a dedicated plug wired to the battery.
Q: Why does my automatic-transmission car have a tachometer? I have no control over it, like I do with a manual transmission.
A: Then you could simply ignore it, right? I still like to know what the engine is doing. And you can still downshift an automatic. Many newer cars have manual functions for the automatic transmission, to boot.
Q: Can a handyman replace an intake manifold on a 1998 Pontiac?
A: You will need a service manual. Try
Q: I just bought a 2007 Chrysler Pacifica Limited, which I love. In the daytime, however, I cannot read the gauges or tell what my speed is. The dark-red pointer against the black background makes it impossible to see as they blend together. At dusk and at night it's great.
I never experienced anything like this. The dealer said that there is nothing I can do. Is there a way to change the dial for illumination, or anything to rectify this?
A: You could turn on the parking lamps, which will light up the dashboard illumination.
Mike Allen is a senior editor for Popular Mechanics magazine. Questions should be sent via e-mail to driveit@nytimes.com.
