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A quart of methanol every six months?

My neighbor, who is a manufacturer of car care products, told me he adds a quart of pure methanol to a full gas tank on his Ford F-150 every six months. He told me that the methanol will keep the injectors and cylinder walls clean and remove all harmful engine deposits. Is this practice helpful or harmful to the engine and exhaust system? I have a 2012 Honda CR-V. Would you recommend this practice for my vehicle?

Rubbish. With the potential of attacking polymers in the fuel system.
If he recommends it, just smile sweetly, nod, and say “uh-huh, uh-huh, uh-huh”. But don’t put methanol in your car. The gas you buy at every fillup has plenty of detergents and additives to keep your engine clean inside aned running properly, without adding anything else.

100% nonsense. Methanol in SMALL amounts is used as a water scavanger (HEET uses it, I think), but it’s not good for much else. And a gallon could cause damage to the plastic/rubber components of your fuel system. I would never do it.

Avoid methanol. It will do nothing useful. Probably won’t hurt anything, but my prior statements are all you need to know.

Pure BS. These are the kind of guys who try to get you to add acetone to your gas tank to improve mileage. In the old days they were known as snake oil salesmen. I wonder what he puts in those “car care” products?

That reminds me…
We are actually overdue for a question about the “miraculous” power of acetone when added to the gas tank.

Is it possible that this quackery has finally died out, only to be replaced by Methanol BS?

I’m surprised we have not yet heard about this amazing advance in automotive technology I saw in the news a few days ago (no, I did not see it in Seattle Times; that’s just the first Google hit that came up):

http://seattletimes.nwsource.com/html/nationworld/2018847643_apaspakistanwatercar.html

A tragicomic state of affairs in Pakistan. Be sure to read the last paragraph!

Ethanol is the grain alcohol used in most gasolines. Methanol is very bad for various things in the fuel system and the engine. This is a really dumb idea, and is likely to just cause the fuel to become more hygroscopic.

In addition to everything said above, this is a good way to void the warranty on most of your car. Bad idea.

He’d be much better off with something less corrosive, such as isopropyl alcohol, or better yet, just grabbing a bottle of Techron and dumping it in.

“He’d be much better off with something less corrosive, such as isopropyl alcohol”

In theory, yes.
However, if take a close look at the bottle of isopropyl alcohol in your bathroom, you will likely see that it is “70% alcohol”, with the other 30% consisting of…water. You may also be able to find 91% isopropyl alcohol in some drug stores (great for cleaning windows, IMHO), but even this product contains water. I think that most of us can agree that introducing water into your gas tank is not a good idea.

There is isopropyl alcohol packaged for automotive use, and this is 100% alcohol. If someone is going to use isopropyl alcohol, it is extremely important to get something made specifically for automotive use. Personally, I prefer to just use a bottle of Techron once or twice a year.

VDCdriver, I meant PURE isopropyl, not the stuff you get in the aisle at your local drug store. Obviously dumping water in your fuel tank is not the greatest idea… Personally I think ammonia works better for cleaning windows…

Agree with everyone here about the BS factor. On top of that, if you were in the store every six months to buy a quart of methanol (or 100% isopropyl, or benzene, or acetone, or nitric acid, etc.) don’t you think Big Brother might start to ask questions?

Well now,
I used to put a pint of transmission fluid in the 80 Bronco’s gas tank to guard against vapor lock.

If methanol was a good thing to put in your gas tank, don’t you think the gas companies would add it to their gasoline and then advertise the benefits of the methanol in their gas?

"I meant PURE isopropyl, not the stuff you get in the aisle at your local drug store. "

I was pretty confident that this was what you meant, but for the sake of those who are not necessarily as knowledgeable, I thought that it was important to clarify the point.