# Acceleration Hesitation after fueling up



## jblackburn (Apr 14, 2012)

When you fill the tank, the car resets timing advance. It tries out the high octane map in the ECU, and when/if it detects knock, it briefly cuts power and dials back timing slightly.


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## tunwno (Oct 3, 2016)

I See good to know it's but not a technical issue.

Thanks for the reply


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## Eddy Cruze (Jan 10, 2014)

Why is it imperative to only give the Gas Cap one click, never really got that, just always do it!


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## NickD (Dec 10, 2011)

One of my kids was buying gas from a station known to have water in their gas, always a problem. Took her awhile to drive a couple of blocks to a busy station that doesn't have this problem. Water is much heaver than gas, settles to the bottom of the tank where the fuel pump picks it up.

You don't get a spark with moisture in your combustion chamber. Misfire, also hard on that after the fact catalytic converter, more problems. If you get a lot of water, engine will stall and you are stranded.

With an FI vehicle can connect a fuel pressure tester, have to know where where the fuel pump relay is at, pull it and use a jumper to run hit, pressure tester has a clear hose and a button on the side of it, run it until you get pure gas out of it.

Happens to the best of us, filled up with gas at a Shell station up north, only got about ten miles away when the engine stalled. Thank the Lord this happened on a road with a shoulder on it, pulled over and switched on the hazard lights. Is a carb vehicle with an engine fuel pump. But I did add an electric pump to it in this motorhome.

Was 1:00 AM in the morning and raining, had to crawl under, I did add clear fuel filters to this thing, had to disconnect the fuel line and yell to my wife to switch on the electric fuel pump, also good I had a flashlight. Also good it has a shower and I had dry clothes, was a mess. Started fine and we got home 45 minutes later.

Told my son about this, he goes up north a lot, gee dad, everybody knows that Shell gas station has water in it, I found out the hard way. 

With lesser cases, can toss in a couple of cans of Heet.


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## obermd (Mar 3, 2012)

Eddy Cruze said:


> Why is it imperative to only give the Gas Cap one click, never really got that, just always do it!


The click tells you the cap is on as tight as it will go. Fuel systems are slightly pressurized which is how the car can tell you when the gas cap is off.


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## Eddy Cruze (Jan 10, 2014)

obermd said:


> The click tells you the cap is on as tight as it will go. Fuel systems are slightly pressurized which is how the car can tell you when the gas cap is off.


Thanks Mike as my Sonata always required more than one click, said 3 clicks


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## obermd (Mar 3, 2012)

Eddy Cruze said:


> Thanks Mike as my Sonata always required more than one click, said 3 clicks


I usually go multiple clicks. I've seen cars that said 3 clicks. GM was able to do it with one.


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## swedgemon (Jan 16, 2017)

Regarding water in your fuel, whether it is gasoline or diesel; At the service station the fuel pump pickup is usually 4 inches off the bottom of the underground or above ground tank. IF there is any water in the tank and it is less than about 2 inches, the water will stay in the tank,, completely harmless. When a fuel tanker makes a fuel drop, however, that water is roiled up off the bottom and can be picked up by the fuel pump, resulting in water in your vehicle fuel tank. If you see a fuel tanker making a fuel drop when you pull in for a fill up, drive on to another service station or get a meal to kill some time until the fuel tanker leaves.


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## obermd (Mar 3, 2012)

swedgemon said:


> Regarding water in your fuel, whether it is gasoline or diesel; At the service station the fuel pump pickup is usually 4 inches off the bottom of the underground or above ground tank. IF there is any water in the tank and it is less than about 2 inches, the water will stay in the tank,, completely harmless. When a fuel tanker makes a fuel drop, however, that water is roiled up off the bottom and can be picked up by the fuel pump, resulting in water in your vehicle fuel tank. If you see a fuel tanker making a fuel drop when you pull in for a fill up, drive on to another service station or get a meal to kill some time until the fuel tanker leaves.


Sediment also gets kicked up.


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## Philb (Jun 18, 2016)

obermd said:


> Sediment also gets kicked up.


I had a Toyota Corolla many years ago that completely died after filling up at a station that was receiving a fuel drop. Had to have the gas tank dropped, lines flushed and fuel filter changed to get all the sediment out that was stirred up during the delivery. I never fill up at a station that's getting refueled. Learned my lesson the hard way!


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## NickD (Dec 10, 2011)

Ha, more problems, ethanol is also heavier than gas, if the tanks do not have impellers, may end up getting pure ethanol, worse yet, 80 octane fuel.

Water table depth is constant, if you live on top of a hill, may have to go down 100-200 feet to get well water, but if on the bottom, as low as 8 feet. Select a gas station on top of a hill. 

Underground tanks are the problem, also affecting aircraft, in the last 10-20 years or so, all the tanks were mounted above ground with a high chain link fence around them plastered with no smoking signs. 

Homogeneous fuels were never a good idea, if you use E10 in you vehicle, you should pick it up and shake it. Nor a good idea in AC refrigerants, mixing two different gases together, if the lighter leaked out, high side pressures were so great, you would blow your system. But yet the EPA approved of both.


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## jcountry (May 30, 2017)

NickD said:


> Ha, more problems, ethanol is also heavier than gas, if the tanks do not have impellers, may end up getting pure ethanol, worse yet, 80 octane fuel.
> 
> Water table depth is constant, if you live on top of a hill, may have to go down 100-200 feet to get well water, but if on the bottom, as low as 8 feet. Select a gas station on top of a hill.
> 
> ...



Ethanol in gasoline is probably the dumbest decision our govt has ever made (and that's a VERY high bar.) 

In addition to it's other problems, ethanol is a very low energy density fuel which requires probably about 1.5 gallons of diesel per gallon of ethanol. We would be far better off if all the fuel involved in planting, harvesting, refining , transporting ethanol were just saved. Ethanol creates way more problems than it solves.


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## NickD (Dec 10, 2011)

For awhile up here E10 was all you could buy, this is what it did to my fuel pump armature, didn't turn very well in my Supra.









This is what it did to my fuel sender.









Do not have photos of the fuel regulator nor the fuel injectors, didn't bother with the fuel filter. No warnings on this, needless to say, I was one unhappy pup.

1986 Volvo boat engine has a large sign by the fuel filler, DO NOT USE ETHANOL. Supra is an 88. Sure can't buy hamburger for a buck for three pounds anymore either. Farmers around here were making more money selling corn outright instead of feeding cattle with it.


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## jcountry (May 30, 2017)

NickD said:


> For awhile up here E10 was all you could buy, this is what it did to my fuel pump armature, didn't turn very well in my Supra.
> 
> View attachment 235322
> 
> ...



I am surprised there haven't been more lawsuits. 

Between the way ethanol wrecks lots of plastics, and the way it draws moisture from the air and contaminates fuel with water, it has wrecked one heck of a lot of components..... But we all know farm subsidies are too big of a political hot potato to ever be criticized.


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## NickD (Dec 10, 2011)

Never heard of anyone that sued the EPA, but sure a ton of citizens were fined by them. What's this jazz you can burn E10 but not E15, both contain ethanol, just seem like E10 would to its damage a bit longer. Also we have over a dozen ethanol plants in our state, each one is different, really no requirements on this stuff.

Kid has an E85 vehicle, tried it once, was more expensive than buying gas for the very poor mileage he got out of it. Wasn't thinking on a trip to Milwaukee, usually fill up first. Ethanol is all you can buy in that city. Sure got a bad mix, only 80 octane, only way I could prevent detonation was to drive a maximum of 40 mph in 3rd gear. And instead of averaging 42 mpg, was more like 17. Plus a very long ride.


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## jblackburn (Apr 14, 2012)

Let's keep political rants in the political section. I'm tired of deleting them. 


Sent from my iPhone using Tapatalk


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## carbon02 (Feb 25, 2011)

May also be due to the carbon in the evap system getting too much gas carry over when the user fills the tank. Fill to the first click and the pump shut's off. People that goose the pump to get very last drop in the system have more evap problems because there's more than just gas vapors that make it into the evap system. There's liquid gas.

When the car starts after refilling one of the first things that occurs is that the evap system pulls vacuum on the carbon releasing the hydrocarbons to the engine. You might have an overloaded evap system.


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