Motormouth: Confused by different types of gas
Q: Can you address the difference, if any, between non-oxygenated versus other gas? One gas station I use has regular octane 87, premium octane 92 and non-oxygenated octane 91. They say their premium gas contains some oxygenates (ethanol) but their non-oxygenated does not contain any ethanol and is even more expensive than the premium. Another brand station says their premium octane 92 is non-oxygenated, which I use in my outboard motor. This is really confusing. Is it one of those "depends" situation?
— G.G., Blaine, Minn.
A: Let’s get back to basics. All gasoline essentially is the same when it leaves the refinery. Additives are then introduced to increase the octane. No matter what is used, the octane rating is scientifically determined. Once upon a time, lead (tetraethyl lead) was blended in to increase the octane, but lead was eliminated beginning in the 1970s because it was a pollutant. It was replaced with MTBE (methyl tertiary butyl ether), an oxygenate. Ethyl alcohol replaced MTBE. Derived from corn, it was cheap and aided the agriculture industry. Some fuel systems, particularly those using carburetors rather than fuel injection, can be damaged by alcohol. Toluene, which is not an oxygenate, increases octane rating and is used especially in racing gas.
Q: I have a new Honda CRV Hybrid and I’m wondering if leaving the key fob in the car when it’s in the garage can keep the computer kind of awake while we’re not using the car? Is it safe to keep it in the car or should we bring it in the house?
— S.B., Coopersburg, Pa.
A: To be on the safe side, I always bring my fobs into the house, at least far enough so that touching the door will not unlock it.
Q: I have a 2017 Kia Cadenza SXL, which I love to drive. It came with low-profile tires, but I do not like the road feel driving over anything but smooth pavement. I tell people that if someone dropped a nickel in the road and I drove over it, I’d feel it in my teeth! I’m also very concerned that, without some adequate tire body under the wheel, severe wheel damage is sure to happen driving through Chicago potholes. Can I replace the tires with a more conventional tire or am I stuck with replacing the same type?
— B.M., Aurora, Ill.
A: You may make the change, but you must maintain the same overall diameter as the original tire and wheel combination. Of course, you will lose the handling performance of your low-profile tires. I like performance, even if I drive over a dime and can tell if it’s heads or tails.
Q: Is there a DIY way to add transmission fluid to a vehicle with a sealed transmission? I have developed a very small leak on my 2013 Volvo C70. It hasn't impacted performance yet, but I would imagine it's only a matter of time before it does.
— J.C., Hartford, Conn.
A: Sealed transmissions are shifting the method for checking the fluid. No longer is there a dipstick. Instead, there is often an inspection plug on the side of the transmission. It helps to have the car on a lift to access said plug. This is how manual transmissions are checked on rear-wheel-drive cars. In some cases, special tools are required. And the fluid isn’t cheap.
(Bob Weber is a writer and mechanic who became an ASE-certified Master Automobile Technician in 1976. He maintains this status by seeking certification every five years. Weber's work appears in professional trade magazines and other consumer publications. His writing also appears in automotive trade publications, Consumer Guide and Consumers Digest.