Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Gas Additive Question

Hey all,

I live in the Midwest, and we are supposed to be getting some bitter temps this next week - record breaking air temps of -6 with 40 degree windchills. Should I be using a gas additive such as HEET during this cold spell? I fill-up with Shell gasoline usually if that helps at all (additive wise).

Last, my car usually sits out most of the night.

I’d love some feedback.


It will not harm anything so go ahead and put it in . I doubt it will make a difference . What would do more good is purchasing one of those portable battery packs. Or you can do what people used to do years ago with the 6 volt systems . They would get up at 1 or 2 at night start the vehicle and let it run for 20 to 30 minutes so it would start in the morning.

Seriously , you live in the Midwest so this can’t be your first time at severe cold .

This is going to be the coldest temps that I’ve ever experienced at a driving age.

1 Like

The sealed gas systems of today’s modern cars have reduced gas line freeze ups common in the olden days due to condensation from unsealed systems. Heet as at least the last bottle I looked at is methanol. I imagine it is similar to ethanol that is probably in your gas. You might check to see if your car has a block heater, It used to be part of the winter package from Ford, And my Trailblazer has one also. They are powered by a standard grounded electrical cord. One ford had a flip cover above the bumper, the other 2 a cord tucked away in the engine compartment. If you are a little knowledgeable it is a cord going to a freeze plug or engine block. I use mine 15 degrees and below, keeps the engine warm for easier starts and less engine wear possibly

Windchill doesn’t affect an engine. Windchill relates the temperature to the wind velocity and what it feels like on the human skin. No matter what the windchill is, -6 Farenheit is the temperature of the engine block. I started my 1971 Ford Maverick when the actual temperature was -21 Farenheit. It started on the first try and this was back in the days of distributor points and carburetors. We had had considerable snow and I had to leave the car outside at the end of the driveway. Today’s cars with fuel injection and electronic ignition should start right up at -6 F.


Perfect! Thanks so much, guys!

Heet makes the water that has condensed into the gas mix with it, runs it through the system, keeps it from icing up; it’s methanol plus some cosolvents to protect plastic and rubber components. Pay $1 more for Iso-Heet, which is isopropanol, a little bit safer. Buy a can of starter fluid, spray ether: it’s cheap, can’t hurt, and you can get high too.

I agree with the battery booster recommendation. I suspect you won’t need anything. I used to live in weather regularly that cold, drove weekly, did nothing special to start up. It’d take a few seconds longer, I’d be a bit more anxious (lived up a dirt road, no utilities, neighbors miles away), but it always started.

Buy a can of starter fluid, spray ether: it’s cheap, can’t hurt, and you can get high too.

That is also a quick way to damage your brain and shorten your life. Not a good idea at all.


Water contamination in fuel is more likely to occur during the transport and storage of your fuel before you get it than from condensation in your car’s fuel tank. It does not really matter where you buy your fuel, water contamination can happen.

It can occur during warm weather as well as cold, but in sub-freezing weather, the symptom is more pronounced (dead stop rather than annoying stutter). Heet has cured my problem two or three times in the 50 years I have been driving.

Explains a lot, doesn’t it? :wink:


There are some things that can go drastically wrong with spray ether, potentially damaging to both the car and you. I’ve only needed it with carburetored cars where the air filter sat right over the carb. You want to use only a short burst of ether and leave the air filter off when cranking as an explosion in the plenum can blow it apart. Dripping a few drops of Colman stove fuel into the carb worked about as well. You may want to research the wisdom of starting fluid on a modern car and if your injection system is working right it shouldn’t be needed.

You-all suffer from irony-deficiency.

Isn’t that rare? A friend who seemed knowledgeable used it. I only used the can I picked up on the side of the dirt road I lived on.

Aren’t all air cleaners on top of their carbs? I know nothing about fuel injection.

I used carb cleaner.

I think the indispensable use of ether is for days so cold the engine won’t ignite gas-air. I’ve started at -17° - that wasn’t cold enough for ether.

Back in my days of ignorance we used spray ether all the time, sometimes shooting successive bursts of it into the carburetor to keep the engine running until it was sufficiently warm to run on gasoline. Backfires accompanied by several feet of flame out of the carburetor were not uncommon and you didn’t want to have your face in the line of fire. The last car I did this with was a '72 Valiant 6 cyl. Not all air filters were directly on top of the carb, my 50 Pontiac had an oil bath air filter separated from the carb by a metal plenum like a big can which you didn’t want to have fill with fumes and explode. I don’t know whether either backfires and explosions might damage air mass sensors, etc., but one should keep risks like that in mind when working on modern, fuel injected cars.


If -6 degrees is as cold as it gets I doubt you’ll have to do anything beyond making sure the coolant offers enough protection. Suggest you ask friends, co-workers, fellow church goers who have lived in that area for some years; they’ll be the ones who’ll be able to offer-up the straight dope on this.

1 Like

Back in 1993, my son had our 1978 Oldsmobile Cutlass at the college he was attending. I had admonished him to keep the gas tank at least half filled during the sub zero weather, but he didn’t take my advice. He started to run an errand one evening and just barely got off campus when the car quit. I had given him an AMOCO motor club membership and he used it to tow the car back to campus. The tow truck driver said that the fuel pump was out and wanted to tow the car to his shop. My son said he didn’t have the money and had the car towed back to campus. When he called me, I had a pretty good idea what way wrong. I figured that the gas line had frozen. I told him to walk down to the grocery store just off campus, buy a bottle of gas line antifreeze and pour it in the tank. I then said to let the car sit until the weather got above freezing as he didn’t need to go anyplace. He went to the store, bought a cheap bottle of gas line antifreeze for 79¢ and poured it in. A few days later, the temperature went up to about 40 degrees, so he decided to try and start the car. He got it to start, it ran roughly for a few minutes, but evened out and was fine. He then filled the gas tank and everything was fine. Another student had the same situation. My son explained what to do, but this student decided to save 79¢. He worked at the stable and figured if he threw warm horse manure under his car, the heat would thaw the fuel line. It didn’t—all it did was make the car smell like horse manure and he had to spend 79¢ for the gas line antifreeze.
Those were the days of carburetors and mechanical fuel pumps that sucked the gas up to the engine. With fuel injection and electric fuel pumps in the tank, cars are easier to start and the gas line is more apt to be purged of moisture.
You probably don’t need to use Heet in today’s cars, but it won’t hurt anything.

That’s abuse. The friend who used it had me spray it into the intake of the air cleaner for a few seconds while he started it…

Thanks; I didn’t know that.

How old is your car? How old is the battery?

I’ve owned a house in the upper Great Lakes area (above the 45th parallel) for over 40 years. I commuted to work at that location, travelling a 72 mile round-trip

I went through decades of winters that had cold spells colder and longer than what you’re talking about. We had mornings in the -20F to -40F range and would go for a week without high temps going above zero.

My cars sat outside every day, all six of them.

Sometimes, some of my cars would make unusual noises, usually loud screaming bloody-murder sounds, when first started and a couple of them would even drip a couple drops of coolant from hose clamps, but before I could totally freak out and try and repair them they would self-correct with temperatures rising to a more normal level. The tires would thump and car jiggle for a mile or so until the tires warmed a bit and became round, again. I learned to just roll with it all.

I never had a car not start. I never added anything to the gas. Shell gas is good (a Top Tier gasoline).

2 Things
One thing I’ve always done is to install the most powerful 12 volt battery, in the correct size, that I could buy, in terms of (CA) cranking amps and especially (CCA) cold cranking amps, shooting for something at least equal to, but often considerably higher than the manufacturer’s installed battery. I made sure posts and cables were clean and protected (usually with grease). I’ve had great luck with Wal-Mart Ever-Start Maxx, gotta get the Maxx. Warranty is good, too. I replace batteries every five years, while they’re still working perfectly.

Another thing is motor oil selection. At least use the manufacturer’s recommended oil for cold weather. At best use Full-Synthetic oil of the correct viscosity, as recommended. FACT: SYNTHETIC OIL FLOWS BETTER AT LOW TEMPERATURES (compared with conventional oil). Synthetic helps the engine crank faster and lubricate better when it’s cold, great for cold starts. Why not just use it all year, eh?

Don’t worry about it. -6 is nothing. If you do nothing you’ll probably be fine. Next time you change the battery or oil, consider the above if you don’t already do that. Since we don’t know what car you’re driving consider backing-in when you park and carry jumper cables and know how to safely use them.

I don’t miss that weather at all. It’s cool here today, mid-sixties, but going back to mid-to-upper-seventies by Friday. I’ll be back up that way when the salt trucks are gone and life returns.

Jman, what make, model, model-year car are you driving?


I think we are talking about two different issues-starting a car in the cold and gas line freeze. If you’ve got a block heater, that helps with a cold start and to make warm ups faster. In the old days, it sometimes would make the difference between starting or not but now with fuel injection, it’s not as much of an issue. It’ll likely start, just the oil may not flow as well for a few minutes. Although I’ll have to say, my neighbor had to have his new truck jumped a couple years ago. It got down around -20 for a while and it sits outside all the time. So you never know.

Back in the 60’s you had to worry about gas line freeze. Where water in the tank would freeze in the lower part of the fuel line and the car would stall. Maybe fuel injection helps now I dunno but probably there is more alcohol in the fuel now so it’s not as much of a problem. Keeping the tank full helps reduce the air in the tank that can condense water so keeping a tank over half full will help. Using Heet won’t hurt but I haven’t really used it in a few years and haven’t had a problem. I wouldn’t hesitate to put a bottle in though if it was well below zero and we’d be out in the hinter lands.

Well as an update, it got down to -29 last night and when I pulled the car out of the garage this morning it had warmed up to -24. I hadn’t used Heet for some years but I did stop and get a couple bottles and put one in each car. It’s not cheap anymore at about $4 but when you think how close you are to death at those temps, I figured no harm no foul.

That weather sounds like normal northern winter weather to me.

I felt close to death in it last winter and especially the winter before that. It didn’t kill me all at once, but I frostbit some toes running the snow blower and they hurt for days, turned purple, and got calloused skin, froze some tissue. It scared me.

That weather was killing me a little at a time, despite thermal boots and Hot Shot socks, rather than all at once. I googled frostbite and got hits from rock climbers and mountain hikers who had cases of frostbite and found that once you freeze flesh it does not tolerate cold well after that. I can attest.

I like all of my extremities too much and decided I can’t do cold anymore. I have not worn anything except shorts, t-shirts/golf shirts and sandals since I got here a couple months ago and nothing’s cold on me. Problem solved. The Grand Prix likes dry roads, too.

Hope the snow load hasn’t collapsed my roof in the north without me there to clear it (I’ve got people sending pictures from up there) , but that’s what insurance is for, right? Ha, ha…