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so that basically says you need a new fuel pump. it could be a direct result of adding the booze to it but you wont know for sure.

it could however be a coincidence. there is a ground strap somewhere back there that will connect to the frame somewhere. it's entirely possible this needs to be taken apart and cleaned up. reconnected to bare metal with a little bit of dielectric grease on the connections, bolted back up and then smothered in dielectric grease after to protect from any further corrosion. it could also be a poor connection of the fuel pumps wiring harness. this is probably not visible and is normally on top of the tank. so it needs to be dropped. do you guys have this ability? surely you can look for this ground strap and make sure it's good.

now I have never worked on one of your trucks or anything this knew so I really cant help you further as I dont have the experience.

good luck.

Al
 

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Can't help but agree with Al, those codes indicate poor performance from the pump in the tank.
Best bet is to have the pressure checked.

Your truck has 2 pumps, the pump in the tank that supplies fuel to engine compartment and the high pressure pump that pushes fuel to the cylinders.

I know the high pressure pump runs around 1500psi, I don't know about the low pressure pump, Ive read 40 to 90psi; but I am not sure.
 

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gee the more I learn about these new engines the less I like them. 2 pumps? is that possibly why there was an "A" and a "B" code? I did not look them up but that had me wondering.

thanks for chiming in Ray. I'm guna go back to the 90's now, when things were simple. HAHAHAHAHA!

have a good night man!
 

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gee the more I learn about these new engines the less I like them. 2 pumps? is that possibly why there was an "A" and a "B" code? I did not look them up but that had me wondering.

thanks for chiming in Ray. I'm guna go back to the 90's now, when things were simple. HAHAHAHAHA!

have a good night man!
Direct injection.... a horrible design in my opinion.

They have a regular pump and then a high pressure pump. And many times when you change the high pressure pumps on direct injection vehicles you have to put the timing at TDC.
 

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@Furious , I not sure it's even a "regular' pump. The function of the low pressure pump is just to get the fuel to the high pressure pump.

Al @thegawd you are probably right about the A and the B codes.

The tank pump is called the A pump when you check the p2635 code. It makes sense that the p018B code applies to the high pressure pump's sensor.
In which case, that pump may not be receiving sufficient fuel flow from the tank pump.
 

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Ray, I missed your post above, about the 60% water that's in the booze.... that could very well be the problem right there. methelhydrate? something like that.... otherwise known as antigel used in diesels and any fuels thought to have been contaminated with water. it works.

I put couple of these bottles in our Mazda that sat for a while and wouldnt start, it started after a day or so but I just dumped it in and walked away. I wasnt thinking about water in the fuel but it was suggested to me.

there is no doubt water in the fuel. it dosent explain the codes but it has to be addressed.

Al
Screenshot_20210714-220242_Gallery.jpg
 

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A lot of liquors have a lot of sugar in them, was this rum that was poured in there?
Rum, brandy and liqueurs (and many other) are high sugar.
That was probably like pouring in a bottle of root beer.

I would bet, that you would need a pump, filter, fuel system overhaul...
Is this a late model truck?

As for running the tank low, I always run down to less than 1/8 tank before filling up. Never had a problem... 100k+ miles, Multiple trucks and cars (all GM of course).
 

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My boyfriend's truck runs great most of the time but sometimes at any speed it could start sputtering and acting like it's running out of gas then we'll put the truck in neutral and shut the truck off and pull to the side and then able to crank it right back up and then it'll run strong and then it'll start sputtering again and sometimes it cuts off by itself and dies but has power and sometimest we cut it off and then we can crank it right back up. Sometimes it takes a minute for it to be able to crank back up.
Does it have fuel injection? Injectors might be clogged. I had it happen where my tank was really low on gas and when I punched it hard in traffic it completely bogged down then didn't run right for a half hour or so. Let it set then it ran fine after that. Don't run the tank so low on fuel.
 

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2012 Silverado 2WD, LT, LMG engine, All stock. 84,000 miles. A Florida truck, zero rust.
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The myth that don't go below the 1/4 mark comes from the early days and as a teenager I heard many tell me don't go below 1/2 tank during the winiter months. It comes from two issues, water at the bottom of the tank from condensation, and that it can caused rust or corrosion inside the tank that can be sucked up. Mine you all this started with diaphragm fuel pumps.
 
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I think the piece that everyone is missing, is that the pickup never moves
If the tank is full, 1/2, or almost empty, the pickup is in the same place with reference to the bottom of the tank.
I would think that the sloshing of a half full tank would cause more bottom crap to more around; but that's what baffles are for.

And pump cooling, hmmmm, that's been debated as long as pumps have been used inside tanks.
First of all, does the pump require cooling?
Yes it does; but only the impeller. The impeller requires lubrication and cooling. And, it gets both from the fuel passing through it.
End of story, exterior cooling by being submerged in a tank of fuel is a falsehood.
If that was a requirement, the low fuel alarm would come on at 1/4 tank, or more.
And don't give me that crap about how GM wants you to run the tank low so the pump fails, they don't want that, and the 3rd party replacement guys don't want that either.
If there was any possibility that low fuel damaged pumps there would be cautions in the new pump box.

However, as I said earlier, impellers require lubrication and cooling. Let the tank run dry and you will kill the impeller.
 

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2019 Silverado HD 2019 Duramax 6.6, Black Crew Cab, 6 Speed.
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All this started after he ran out of gas one night and he was trying to make it like a hundred yards up the street to get to the gas station and he had a couple old bottles of liquor in the back of his truck that had been in a fire (long story) and he poured them into the tank trying to see if it would make it to the store and that is what started all of this
Its also easier to take the bed off of a truck to change the fuel pump than to drop the fuel tank in my opinion.
 

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on my Burb it's only 2 bolts, 3 screws on the filler neck and oh 1 ground strap to drop the 42 gallon tank. I however have a transmission jack which makes dropping the tank so simple. I can drop it, do whatever in the tank and put it back together in 30 mins. but fuel vapor isn't something to mess around with. I use an electric impact gun but I wouldnt if there was fuel vapor. 1 spark and KABOOM. so think about it and keep a proper rated fire extinguish within an arms reach.

be safe.

Al
 

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Al, like your Burb, my Av is an easy job, if the weight is manageable. I don't have a tranny jack, I had to weight until the fuel was almost at empty.
To be on the safe side, I replaced the straps; but I probably could have cleaned them and with a little paint they would have been good for a few more years.
The hardest problem I had was getting the new pump into place so I could get the ring on
 

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I replaced everything cuz it was all original. I took the new straps and painted them with like 6 coats of automotive paint and even clear coated them a couple times. I smothered everything else in grease... even the tank LMAO I even painted the plastic shroud cuz with everything else new it looked like crap.

my sierra needs a pump and it also need both cab corners. so for this I am removing the box entirely.
 

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I always took the bed off. Its easier and safer. It’s just my preference.
 

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Discussion Starter · #37 ·
Its also easier to take the bed off of a truck to change the fuel pump than to drop the fuel tank in my opinion.
I would agree with you because that's what I did with my Colorado. It was a piece of cake cause the bed is so light. However, his truck is a lot bigger and he has a full toolbox and equipment loaded in the back. The circumstances just don't make that as easy as it seems.
 

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Discussion Starter · #38 ·
Okay, so he put the alcohol y'all suggested into a 1/4 tank. He said it drove perfectly until it slipped his mind that he was going to drive it all the way out and filled his tank. Not even a mile up the road his truck kept spuddering until it finally shut off. He didn't want to damage his starter again so he just pulled it home.
 

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Discussion Starter · #40 ·
A lot of liquors have a lot of sugar in them, was this rum that was poured in there?
Rum, brandy and liqueurs (and many other) are high sugar.
That was probably like pouring in a bottle of root beer.

I would bet, that you would need a pump, filter, fuel system overhaul...
Is this a late model truck?

As for running the tank low, I always run down to less than 1/8 tank before filling up. Never had a problem... 100k+ miles, Multiple trucks and cars (all GM of course).
It was a couple different kinds of liquor not really sure which ones.
 
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