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Improvised engine heater

Okay, so it’s below zero outside, and our 05 Passat won’t start (battery is not dead…yet). Is there some sort of SAFE way to warm the engine, gas line, fuel pump and such other than sending my husband outside to sleep on top of the hood? It’ll cost a fortune to get a tow truck out here!



blow dryer or electric blanket - but don’t let any wires touch the battery or alternator and make sure you remove all these before trying to start the car. In the future, you can get heating plates that plug in at the auto parts store. You can also put “HEET” in the gas tank when you fill up to keep the gas from freezing - find at any gas station or grocery store.

If the sun shines on the front of the car and the temperature gets above 15 degrees, it will probably start. Northern Maine was cold too. A weak heater could help as long as it’s not right on top of plastic, or really close. So, if you have a sunny spot at around 10:00 AM you are in luck if you can get the car faced in the right direction, or even sideways to the sun. Your car probably needs a head heater if one is supposed to be installed there. The people who sell and install those things will have a manual that tells them where it goes.

If the battery is 3-5 years old then maybe it’s getting weak and needs to be replaced.
In cold climates like this do not use heavy engine oil as this can cause the starter to work harder and put more of a drain on the battery.
You might consider installing an engine block heater also.

Remove the battery and bring it inside…Change your oil and use 0W-20 synthetic. Have a block heater installed on the engine.

A picture of the blow drier attempt would be hilarious.

Electric blanket may help but I don’t see the hair dryer. A heating pad wrapped around the battery, or bringing the battery inside for an hour or two may help.

Question: Is the engine “turning over” or cranking, but just won’t “catch”? Or is the problem that the engine won’t turn? If it won’t turn, a jump start may be the best alternative. If it needs warming up, unless you specifically know what’s frozen (like what part of the fuel line), it will probably be pretty hard to get everything warm enough unless you can push or tow it into a heated garage. You can try one of the block heaters that go in the dipstick tube, and putting some gas line antifreeze in the tank may help prevent this from happening again, but probably won’t reach any ice that’s in the fuel lines.

I’d be wary about using any heat source large enough to warm the whole vehicle outdoors–that’s how Darwin awards are won. You could try (carefully and with the dryer plugged into a GFI outlet) following the fuel line and warming it along it’s length while having someone intermittently try to start the car.

To about -15F should not pose a problem except if battery is weak or you have a running problem.

When I was in graduate school in NW Ohio I experienced some pretty cold winters . . . don’t know if it is characteristic of NW Ohio, but it was when I lived there. Anyway, a neighbor had an old VW Bug (air-cooled) and had difficulty starting it in the winter. He rigged-up a setup which put one of those little square box heaters (Pelonis?) half on the back bumper and half into the engine compartment, shooting warm air on the engine. With the engine “hood” partially closed, he put an old blanket on the “hood”, and since the inside/underneath of the motor areaa was somewhat sealed, it was a pretty much closed box. It worked every time, 10 minutes or so was all it needed, he started it while the setup was still in there . . . which I thought was a bad idea, but he never seemed to have a problem with it. Once running, the old VW ran well, no stumbling or stalling. I talked him into a tune-up one week, and the next week the Bug got totalled sitting parked near the highway. Rocketman

Right now it is -22F where I live and the car will start because we are prepared for this by having synthetic oil in the engine, have put a trickle charger on the battery and the ignition sytem (spark plugs) are up to scratch.

One of the best ways to heat up the underhood compartment is using a 500-750 watt heat lampwithj a clamp that can fasten to the underside of the hood or on the fender braces.

Make sure the lamp does not touch anything. Partially close the hood, leaving about a foot gap at the front, and the radiant heat of the lamp will quickly warm up the engine. If you are really serious you can buy an infrared heat lamp.

My kid brother in college had an old Dodge and he used the sports section of the paper, set it on fire and closed the hood. The fire dried out the wires without setting the car on fire. I DO NOT RECOMMEND THIS TO ANYONE!

As others mentioned, make sure you have thin oil in the engine. A 5W30 or 0W30 synthetic is best.

Good luck and a Happy New Year!

Hey, we used to use blow dryers to heat up the O-rings on the air brake knob on the charter buses at the ski resorts. It was so cold there was too much blow-by and the brakes wouldn’t release. Thought it would work on the battery. But my blanket idea was a good one.

The old mechanic’s drop ( work ) light with a good ol’ incandescent bulb is the next best thing from the heat lamp idea.