Motormouth: Spark plugs popping out of aluminum heads

Q: My 2012 Honda Fit with 70,000 miles had a spark plug pop out. The spark plugs have never been changed. The mechanic said this is a common problem with lighter engines. Is this common?

R.M., Yardley, Pa.

A: Spark plugs blowing out of aluminum heads is becoming more common. Honda and Ford seem to have more than their share. The fix requires new threads in the cylinder head and that requires a thread insert. The Helicoil brand name is synonymous with the repair kits that usually have a thread tap, an installation tool and some inserts. Some kits include the necessary drill bit.

Q: Are there still power outlets on new cars like my 12-year-old Ford Taurus lawn ornament? The power outlet was similar to the cigarette lighter orifice. I hate my car.

R.M., Crystal Lake, Ill.

A: Although cigarette lighters (and ashtrays) are disappearing, power outlets are thriving. We are discovering them all over the vehicle: in the dash, in the center console, various places in the rear seat area and even in the trunk or hatch area. Some only operate when the key is on while others are always hot. You won't have any trouble finding a place to connect your radar detector or blender for margaritas when tailgating at the Jimmy Buffett concert.

Q: I bought a Toyota RAV4 in 2013, but it didn't come with a compass. I have tried new store-bought compasses with no luck. Why can't I find a compass that will work in my car?

A: Most compasses found in retail stores are unreliable. Automobiles have lots of steel that interferes with the compass. Add in the various electrical fields created and you quickly understand the problem. One solution is to get a marine compass, but most are rather expensive. A cheap alternative may be to download a GPS-based compass app for your smartphone.

Q: In a previous column you stated the SJ oil classification to be more current than SM. Wouldn't SM be more current then the SJ?

P.G., Plainfield, Ill.

A: Oops. We got it backward; "N" only comes before "M" on the keyboard. Each new American Petroleum Institute oil classification is the next letter of the alphabet. The only exception to that rule is that the letter "I" was not used to avoid confusion with the numeral "1." The most recent classification, introduced in 2010, is SN (not SM, which was a fat-fingered typo). It offers better high-temperature protection from piston deposits and better sludge control than SM.

Q: After our son in Albuquerque, N.M., recently bought a new Mustang with an eight-cylinder engine, he was told the motor required synthetic oil and the cost of an oil change would be $145, mainly because of the cost of synthetic oil. Is synthetic oil that expensive?

A: If you shop around, you may find that Motorcraft full synthetic oil costs roughly $10 per quart. The 5-liter Mustang engine requires 8 quarts so, right there, you are looking at $80 before you add in the oil filter. Yeah, synthetic motor oil is expensive.