MMO works for this application

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MN
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Bought when new a 04 explorer with the 4.0 engine. I usually use Costco or Kwik Trip gas. Every 3 to 4 years after filling the gas tank, the gauge will not go to the full mark. You have to drive for 20 to 30 minutes before it reaches the full mark. With trial and error I have found by using the recommended amount of MMO in the gas it will take about 2 tank full's to go back to registering the correct amount after the fill. I'm not a mechanic but a better DIY after owning a Ford product.
 
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34,647
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NY
Over the years I had MMO get the gas gauge to work on two Fords, from the 60's and a 72 Plymouth Satellite. If there is some kind of foreign matter, varnish, etc. causing it to malfunction it probably cleans it up. Once they started working again I would add it to the fuel at each fill up, [if I remembered] and they worked for several years after.
 
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Champlain/Hudson Valley
Don't confuse this post with data. I've read several posts involving a good cleaner (Chevron Techron) "getting fuel gauges to work again". Baffles in gas tanks can become unattached and foul the float. It was common in Saabs of my era. I just bought an '05 Ranger with the same engine. Given the way it drinks fuel (think Niagara Falls) I'd bet the fuel gauge hardware would WEAR OUT before anything else could happen.
 
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982
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SE PA
With pretty much all fuel having up to 10% ethanol it might be good practice using a little bit of MMO from time to time. It won't harm anything for sure.
 
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CA
Originally Posted by diyjake
With pretty much all fuel having up to 10% ethanol it might be good practice using a little bit of MMO from time to time. It won't harm anything for sure.
Does MMO remove ethanol?
 
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1,776
Location
Kingston
Originally Posted by Kira
Don't confuse this post with data. I've read several posts involving a good cleaner (Chevron Techron) "getting fuel gauges to work again". Baffles in gas tanks can become unattached and foul the float. It was common in Saabs of my era. I just bought an '05 Ranger with the same engine. Given the way it drinks fuel (think Niagara Falls) I'd bet the fuel gauge hardware would WEAR OUT before anything else could happen.
So what you're saying is, don't bother trying it, even though it worked for several people, some of them having repeatable results? You admit to seeing many people claiming the same thing, but are you trying to say they're all imagining it? Or that it's coincidence that it started to work again every time shortly after they tried techron or MMO? I remembered there being a gm tsb when I worked at the dealership years ago so I just looked it up and found someone posted it ... "HOWEVER, GM has just issued a TSB on this problem that applies to ALL GM vehicles and blames the high incidence of sending unit failures on high levels of sulfur in gasoline. The sulfur corrodes the sliding resistor mechanism and produces erratic and inaccurate gauge readings. To address this problem, GM has released a FUEL TANK ADDITIVE. According to GM TSB #06-00-89-07BB, you should purchase a bottle of GM Fuel System Treatment Plus (part #88861011 for GM brand, 88861013 for AC Delco brand, and 88861012 in Canada) and add it to your tank at every oil change. The additive cleans the sulfur corrosion from the sending unit and prevents new corrosion by laying down a protective film. The additive also removes engine deposits." So maybe gm is imagining this fix also? Obviously it won't help if the sensor is just faulty but if it's deposits these additives could work over time.
 
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34,647
Location
NY
Originally Posted by caprice_2nv
Originally Posted by Kira
Don't confuse this post with data. I've read several posts involving a good cleaner (Chevron Techron) "getting fuel gauges to work again". Baffles in gas tanks can become unattached and foul the float. It was common in Saabs of my era. I just bought an '05 Ranger with the same engine. Given the way it drinks fuel (think Niagara Falls) I'd bet the fuel gauge hardware would WEAR OUT before anything else could happen.
So what you're saying is, don't bother trying it, even though it worked for several people, some of them having repeatable results? You admit to seeing many people claiming the same thing, but are you trying to say they're all imagining it? Or that it's coincidence that it started to work again every time shortly after they tried techron or MMO? I remembered there being a gm tsb when I worked at the dealership years ago so I just looked it up and found someone posted it ... "HOWEVER, GM has just issued a TSB on this problem that applies to ALL GM vehicles and blames the high incidence of sending unit failures on high levels of sulfur in gasoline. The sulfur corrodes the sliding resistor mechanism and produces erratic and inaccurate gauge readings. To address this problem, GM has released a FUEL TANK ADDITIVE. According to GM TSB #06-00-89-07BB, you should purchase a bottle of GM Fuel System Treatment Plus (part #88861011 for GM brand, 88861013 for AC Delco brand, and 88861012 in Canada) and add it to your tank at every oil change. The additive cleans the sulfur corrosion from the sending unit and prevents new corrosion by laying down a protective film. The additive also removes engine deposits." So maybe gm is imagining this fix also? Obviously it won't help if the sensor is just faulty but if it's deposits these additives could work over time.
I'd be trying an additive as a remedy, before dropping a gas tank if I had the problem with a vehicle that's out of warranty.
 
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982
Location
SE PA
Originally Posted by ad244
Originally Posted by diyjake
With pretty much all fuel having up to 10% ethanol it might be good practice using a little bit of MMO from time to time. It won't harm anything for sure.
Does MMO remove ethanol?
Not that I know off, more like fuel treatment.
 
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15,032
Location
Upper Midwest
Originally Posted by diyjake
Originally Posted by ad244
Originally Posted by diyjake
With pretty much all fuel having up to 10% ethanol it might be good practice using a little bit of MMO from time to time. It won't harm anything for sure.
Does MMO remove ethanol?
Not that I know off, more like fuel treatment.
No, you can't remove something with an additive unless it reacts and causes it to precipitate. And you don't want that.
 
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1,479
Location
Northeast Nebraska
I use Star Tron in my 89 Sierra to keep the gas gauge smooth, other wise it won't read full when full and then all of a sudden jump up to full when it should be 1/2 or 3/4 then when it gets down to a quarter of a tank it will bounce between 1/4 and empty. A couple ounces of Star Tron every fill up keeps it working like it should. Although sometimes it still bounces around when it's near a !/4 tank but I think that has more to do with is sloshing around in that 32 gallon tank.
 
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156
Location
MN
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This is probably the third time I have tried the MMO to correct it which it did. It seemed to take a little longer than normal maybe because of the cold weather. In the past it was during the summer. I usually buy a quart at a time and use it till it runs out, and than tend to forget about it. Should probably add on a regular basis.
 
Messages
1,479
Location
Northeast Nebraska
I ran out of Star Tron a few months ago and I'm half way thru tank 3 without adding any and the gauge it still working correctly. I've also been using Shell TT E10 fuel for the last couple years since the price spread for E0 is .35 and just isn't worth the extra mpg I was getting. So my plan is to run it with out any Star Tron and see if the problem comes back. I'm hoping that the TT fuel is enough to keep it working.
 
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Messages
243
Location
Occupied California
There was considerable discussion on the Nissan 370Z Forum regarding the fuel gauge not showing full even when filled to almost overflowing. It was eventually determined that a dose of MMO would solve the problem and be good for several fuel tanks before the problem reared its head again. At which point another dose of MMO would return the gauge function to normal. I always ran top tier 91 octane gas but something was causing the sending unit in the tank to not operate properly. MMO is fairly inexpensive so I added a few ounces to the tank about every 3rd or 4th fill up as a PM or when I noticed the gauge wouldn't read full. It works.
 
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1,776
Location
Kingston
I'm running nothing but top tier Esso in my cars now to try to keep the carbs from plugging up without spending a fortune on e0 91 octane. The price difference is so much here I'd probably have to get like 20% better fuel mileage to make up for it. I use e0 in the summer car before parking it for winter. The gas gauge in my Caprice worked fine until I replaced the instrument cluster and the replacement gauge twitches back and forth by 1/8 of a tank (electrical problem in the gauge), the Cutlass gauge has always been inaccurate but it's mainly predictable. (Full starts at 3/4 and then it climbs to full as you drive for a while then starts to drop again. Below 1/2 seems accurate). It has never changed so I don't think it has anything to do with buildup. That seems to be more of a problem with more modern vehicles.
 
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