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Discussion Starter · #1 ·
I have a 2014 Chevy SS, it has 40k miles and long story short I accidentally added one and a half gallons of 110 octane LEADED gas to my car. After realizing it was LEADED gas I filled the rest of the tank (18 gallon tank) with 93 octane premium unleaded gas, are my catalytic converters and 02 sensors going to get damaged?? What do I need to do ! 馃槥
 

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Welcome. Hope some one has a good answer for you. Removing our tank to drain and flush requires dropping the rear cradle. Not a fun job. Good luck as the lead will definitely damage the converters. Maybe not kill, but damage for sure. To what extent is an unknown.
 

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I don't have an answer for you, but go post this question on the Corvette Forum in sub-forum 'C6 General Discussion'. You'll get 20 responses before you get one here.
 

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Well, if it were me, before I ever considered dropping the tank, I'd consider simply diluting it to the point of inconsequence. If you have the storage means, you could siphon the tank out, and then refill it. Then repeat the process once more. (I know, a lot of storage is required).
Looking at the dilution rate with a few assumptions, it would go something like this . . .

Currently, you have 16.5 gal Unleaded / 1.5 gal Leaded => 11:1 ratio (1.5 gal lead in tank)
Siphoning the tank down to 1 gallon remaining (you'll never get it all out) and then adding 17 fresh gas back yields:
1/11 gal leaded gas / 17+10/11 unleaded gas => 197:1 ratio (11.65 oz. leaded still in tank)
Again, Siphoning the tank down to 1 gallon remaining (can't get it all out) and then adding another 17 fresh gallons gas back in yields:
1/197 gal leaded gas / 17+196/197 gal unleaded gas => 3545:1 ratio (0.65 oz. leaded gas in tank)

At that point you'd have a mere 0.65 ounces of leaded gas remaining in the tank, which is but a "cap full" and could likely be disregarded.
 

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I would pump it out before you run it through the engine and risk damage to your cats / o2 sensors.
 

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I would pump it out before you run it through the engine and risk damage to your cats / o2 sensors.
Right, and the more times you pump it out, the greater the final dilution factor will be. You'll never get it all out without completely evacuating the fuel system from A to Z, so at some point, you have to find a dilution factor that you feel comfortable running through the engine. Like I said, 2 dilution cycles leaves just a cap full of leaded in 18 gallons. I guess you could run another cycle if you still weren't comfortable with that. Running the numbers, it looks like that would leave you with 0.036 ounces (approx 1 mL or 20 drops) still left in the tank. Of course, you also have 51 gallons of gas that you siphoned out of the tank left over to deal with too.
 

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Discussion Starter · #7 ·
Well, if it were me, before I ever considered dropping the tank, I'd consider simply diluting it to the point of inconsequence. If you have the storage means, you could siphon the tank out, and then refill it. Then repeat the process once more. (I know, a lot of storage is required).
Looking at the dilution rate with a few assumptions, it would go something like this . . .

Currently, you have 16.5 gal Unleaded / 1.5 gal Leaded => 11:1 ratio (1.5 gal lead in tank)
Siphoning the tank down to 1 gallon remaining (you'll never get it all out) and then adding 17 fresh gas back yields:
1/11 gal leaded gas / 17+10/11 unleaded gas => 197:1 ratio (11.65 oz. leaded still in tank)
Again, Siphoning the tank down to 1 gallon remaining (can't get it all out) and then adding another 17 fresh gallons gas back in yields:
1/197 gal leaded gas / 17+196/197 gal unleaded gas => 3545:1 ratio (0.65 oz. lead in tank)

At that point you'd have a mere 0.65 ounces of leaded gas remaining in the tank, which is but a "cap full" and could likely be disregarded.
Thanks for the advice and breakdown of what to expect.
 

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Discussion Starter · #8 ·
Right, and the more times you pump it out, the greater the final dilution factor will be. You'll never get it all out without completely evacuating the fuel system from A to Z, so at some point, you have to find a dilution factor that you feel comfortable running through the engine. Like I said, 2 dilution cycles leaves just a cap full of leaded in 18 gallons. I guess you could run another cycle if you still weren't comfortable with that. Running the numbers, it looks like that would leave you with 0.036 ounces (approx 1 mL or 20 drops) still left in the tank. Of course, you also have 51 gallons of gas that you siphoned out of the tank left over to deal with too.
Thanks for the feedback.
 

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Is it even possible to siphon fuel out of our tank?
I can't say I have tried in on the SS, but I have successfully on other modern fuel tanks. It required a smaller diameter of tubing/hose that could pass down the smaller orifice and through the obfuscating bits. Granted, it was a very slow process given the small size required.
 

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I don't see 1.5 gal in a full tank being a problem. I get called many times telling me one of our driver pumped a few gallons of gasoline in the diesel tank. If it is no more than 3 gallons, I tell them to fill up the rest with diesel and continue with work. I've yet to change an injection pump or injectors. And this is on modern Cummins, Mercedes & Isuzu diesel engines with DPF & SCR system. Much more sophisticated than our LS3 fuel & exhaust system.

I also give the same advice when the gasoline drivers pump diesel in their gas tank.
 

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I don't see 1.5 gal in a full tank being a problem. I get called many times telling me one of our driver pumped a few gallons of gasoline in the diesel tank. If it is no more than 3 gallons, I tell them to fill up the rest with diesel and continue with work. I've yet to change an injection pump or injectors. And this is on modern Cummins, Mercedes & Isuzu diesel engines with DPF & SCR system. Much more sophisticated than our LS3 fuel & exhaust system.

I also give the same advice when the gasoline drivers pump diesel in their gas tank.
I agree, not enough to be a problem.....
 
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Two things.
Our tank is a saddle style - not sure how much can be siphoned from the filler neck which is long and convoluted anyway. Difficult for sure.
Even very small amounts of tetraethyl lead is death to 02 sensors and detrimental to catalyst in the converters. Diesel contaminated unleaded gasoline is nowhere near what the OP is dealing with.
 

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Two things.
Our tank is a saddle style - not sure how much can be siphoned from the filler neck which is long and convoluted anyway. Difficult for sure.
...
Hmm, not disputing that it's a saddle at all, but this just made me wonder how the fuel pump picks up from both sides of the tank then; does it have more than one pickup?
I'm sure I have driven my car quite low on fuel before, certainly down to the last 3/4 gallon (of the18) or so tank capacity.
 

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As have I, but siphoning from the filler isn't taking it the same as the pump does. May have a crossover passage or two draw tubes, not sure and I'm too lazy today to look at the service manual.
 

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I would run it with a dilution mixture of unleaded.
If the syphon does work: pull the fuel rail at the engine and cycle on and off until you drain out what you feel is safe then full with unleaded to dilute.
 
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