

🚗 Elevate your engine’s game with Marvel Mystery Oil — the secret pros swear by!
Marvel Mystery Oil MM12R is a universal-fit engine additive that cleans and lubricates fuel injectors and carburetors, reduces varnish and gum build-up, prevents valve sticking and clatter, and protects oil from extreme temperature breakdown. Sold as a convenient 2-pack of 16oz bottles, it enhances fuel economy, smooths engine performance, and extends engine life for cars, trucks, and small engines alike.






| ASIN | B0725JQXKS |
| Automotive Fit Type | Universal Fit |
| Best Sellers Rank | #5,635 in Automotive ( See Top 100 in Automotive ) #18 in Engine & Oil Fluid Additives |
| Brand | Marvel Mystery Oil |
| Customer Reviews | 4.8 4.8 out of 5 stars (1,457) |
| Date First Available | May 11, 2017 |
| Global Trade Identification Number | 00074660507216 |
| Item Weight | 0.01 ounces |
| Item model number | 50721 |
| Manufacturer | Marvel Mystery Oil |
| Manufacturer Part Number | 50721 |
| Package Dimensions | 9.33 x 7.87 x 2.52 inches |
| Size | 16 oz. (2-Pack) |
| UPC | 077874507218 074660507216 |
| Vehicle Service Type | Car |
G**N
Best Price for a 2 pack and it WORKS!
I've always wondered about Marvel Mystery Oil as I've seen reviews along with various YouTube videos about the benefits of this product. So I decided to give it a try. Make sure you follow the instructions on the label for the application your using it for! It doesn't take a lot, whether adding to your oil or your gas First I put some in my gas tank at the recommended amount (4 oz per 10 gallons). Most people do this 2 to 3 times to get the full benefits of the product. So a 16 oz bottle of Marvel Mystery Oil would treat 40 gallons of gas. It has improved the performance of my 2011 KIA Sorento 4 cylinder after using on 40 gallons and I'm going to change the spark plugs now. On my significant others 2002 Toyota SR5 4runner, we've had issues with 3 of the idiot lights always staying on, which I've read could be the O2 sensors. On the 3rd application (I used a bottle, 4 oz per 10 gallons, 4 times in a row) those lights went off and have stayed off for 3 months now! Did it clean out the O2 sensors? I'm going to say yes because they have been on for a full year! Then I added some to my KIA's 4 cylinder oil. You can add or replace 20% of your oil so if you use 5 quarts of oil, you could replace 1 quart of oil with Marvel Mystery Oil. I had changed my oil around 3,000 miles ago with full synthetic Castrol Edge along with using a high dollar synthetic oil filter. This synthetic oil has been so "clean and clear" that it was difficult to read the level on the dipstick. But it was like a 1/2 quart low. So I added 10 oz directly to the motor. 200 miles later, the oil went from almost being clear to black!! So it definitely was cleaning something. I drove it 300 more miles and then changed the oil and filter. I had read that you should add this product like 500 miles before your scheduled oil change and now I see why! My KIA is purring like a kitten and I'm getting 3 more miles per gallon on the highway (78 on the interstate). Finally, I had added some (4 oz) to a 1 gallon gas container for my lawn mower and the some to the 1 gallon mixture of gas/oil for my old Toro snowblower. The snowblower had been running rough and occasionally dying on me. By the 2nd time I refilled the Toro's gas tank, that 25 year old Toro was once again running like it did when I got it new! I'm serious here! Then this Spring (right now), it naturally was added to the lawn mower. I just got done mowing the yard for the 2nd time this year and it uses 1 tank of gas to get the entire yard done. When I went to start it up, it started on the first pull as usual. But a HUGE gray smoke cloud came out of the exhaust! And it's never done that before. But it's purring like a kitten too! I'm no mechanic but am rather handy. Just installed a new capacitor on the outside air conditioner as it wasn't cooling. And it solved the issue. Marvel Mystery Oil says it improves compression, power, & MPG, along with lubricating upper cylinder for smoother idling along with keeping engines clean from sludge. Based off my results or experiences. I would have to agree 100%. I'll keep adding a little to the gas now & then. But if I add to the oil, I will only due that like 200 miles before the next oil change. I recommend trying!!!
T**L
Great product
Age old product works great on injection system both gas and diesel
G**G
Mystery oil
Great product, as described.A+
B**E
Excellent product at a good value
I have been using Mystery oil for over 30+ years with every oil change to keep the engine well lubed and the internals clean from sludge. I purchased and older truck that had low oil pressure, the engine is known for bad pressure sensors that get gummed up. I did an oil change and added 16oz of mystery oil then started driving the truck. The oil pressure gauge was running 0 to 10 psi before the oil change and after it started to climb up 20 to 30 each time I drove it got better. After a few hundred miles the gauge was reading 40 to 60 psi where it should be. I have not had an problem with low oil pressure since it keeps the internals clean and well lubed. I am very happy with the product and its multi uses I would recommend it.
D**S
Old school stuff, still works.
Works great! I don't know what's in it. It's a mystery.
A**R
Good product
Works great
F**E
Nene
Excellent
G**S
Siento diferente el carro muy bien
M**I
Pour le moment impossible de vérifier efficacité, un galon = 4.8 litre . Manque 4 litres
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