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Costco gas and P0340

HazMatFool

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So I've had this code pop up and disappear within a day. I have the extended warranty, so I visited the dealership, and the first thing the service rep asked was if I had filled my tank that day or the day before with Costco, Walmart, or HEB (local grocery store) gas. I told him that I had filled up with Costco gas the day before. He told me that he sees that code with poor-quality gas and to never get gas from the aforementioned stations. He cleared the code and recommended that I add a fuel additive. I had some B&G, so I went ahead and added that to my tank. I rarely, if ever, get gas from Costco and mainly visit QT, Shell, or Valero. I was trying to remember if the past times the code had popped up I had purchased fuel from Costco, but I don't know if the dates correlate.

Has anyone else experienced this, or was he just blowing smoke up my ass?
I use Costco gas Reg Unleaded in my 2020 JTR and I have NO problems, codes or anything negative! It's great gas and has been for decades... yes, I am as old as the dirt at the base of the cross. 😆
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Ramboy

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So I've had this code pop up and disappear within a day. I have the extended warranty, so I visited the dealership, and the first thing the service rep asked was if I had filled my tank that day or the day before with Costco, Walmart, or HEB (local grocery store) gas. I told him that I had filled up with Costco gas the day before. He told me that he sees that code with poor-quality gas and to never get gas from the aforementioned stations. He cleared the code and recommended that I add a fuel additive. I had some B&G, so I went ahead and added that to my tank. I rarely, if ever, get gas from Costco and mainly visit QT, Shell, or Valero. I was trying to remember if the past times the code had popped up I had purchased fuel from Costco, but I don't know if the dates correlate.

Has anyone else experienced this, or was he just blowing smoke up my ass?
Shell is the best.
 

MrBones

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Everybody in a specific refinery region gets the same spot market gas delivered to their brand specific gas station. It is the add pack if any that makes the difference between brands but is not required.
 

MrBones

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Everybody in a specific refinery region gets the same spot market gas delivered to their brand specific gas station. It is the add pack if any that makes the difference between brands but is not required.



True. I worked in refinery design and construction in Southern California for over 20 years. All the refineries pump gas to local tank farm. The proprietary detergents are added at the tanker truck fill station. I personally don't use Costco because between the drive distance and the wait time in the insane lines I'd burn up any saving. But, otherwise, I would trust it.
The lines around here remind me of the gas embargo of the 70's
 

camss69

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Lines? You mean Costco lines? They move pretty quick. I haven’t seen lines anywhere else around here in NorCal

The other thing nice about Costco if you use their credit card they give you 5% back on Costco gas. I think 4% everywhere else you buy gas.
 

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Same here in Northern Kentucky. Not much in the way of lines, very little waiting. COSTCO gas can be $1 cheaper than surrounding stations, and there's the 5% thing. It is one of the best values going IMHO
 

MrBones

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Lines? You mean Costco lines? They move pretty quick. I haven’t seen lines anywhere else around here in NorCal

The other thing nice about Costco if you use their credit card they give you 5% back on Costco gas. I think 4% everywhere else you buy gas.
Not the store lines. Gas station lines. At one store they had to block out a section of the parking lot to avoid congestion. At another the lines spill out into the street and block traffic.
 

Over The Hill

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So I've had this code pop up and disappear within a day. I have the extended warranty, so I visited the dealership, and the first thing the service rep asked was if I had filled my tank that day or the day before with Costco, Walmart, or HEB (local grocery store) gas. I told him that I had filled up with Costco gas the day before. He told me that he sees that code with poor-quality gas and to never get gas from the aforementioned stations. He cleared the code and recommended that I add a fuel additive. I had some B&G, so I went ahead and added that to my tank. I rarely, if ever, get gas from Costco and mainly visit QT, Shell, or Valero. I was trying to remember if the past times the code had popped up I had purchased fuel from Costco, but I don't know if the dates correlate.

Has anyone else experienced this, or was he just blowing smoke up my ass?
Nope, and I buy from Costco, Wal-Mart, and Fast-Stop. No issue on.any of my 3 jeeps.
 

Guns_N_Rosaries

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As someone who used to make gasoline... I just get mine from walmart or where ever is cheapest. There are definitely better detergents and additives in "top tier" gas stations, but I just throw in a bottle of techron every few months, and everything is fine.

That guy probably thinks he's telling you the truth, but he's wrong. Gasoline has to meet standards, and is regularly tested. The issues with bad gas are from independent stations that are sketchy, and from mistakes when refilling the storage tanks (like the driver filling the premium with diesel accidentally).
 

In3briatedPanda

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our Lexus only gets gas at costco (otw to work for my wife is the main reason). I fill up at a circle k otw home or Parkers gas stations.

the jeep owners manual states to not use additives.

Im a big advocate for BG products. Their ATC+ stopped the torque shudder in my 02 grand marquis.

i also run the ethanol, moa, and the 44k in all my vehicles minus the Lexus (lease/work perk we rarely have one past 20k miles.) Stuff can get pricey at the dealer, our rep gives them to me for free when i ask.

I have heard that walmart has lower tier gas. I find it hard to believe that the bigger stations would sell a diluted product, which in terms hurts their business and bottom line. Greed is greed is though.

My neighbor and a coworker used to fill up at a circle k near our homes, both of their Ram vehicles have had injector replacements and the common denominator was that gas station.
 

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Wheelin98TJ

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our Lexus only gets gas at costco (otw to work for my wife is the main reason). I fill up at a circle k otw home or Parkers gas stations.

the jeep owners manual states to not use additives.

Im a big advocate for BG products. Their ATC+ stopped the torque shudder in my 02 grand marquis.

i also run the ethanol, moa, and the 44k in all my vehicles minus the Lexus (lease/work perk we rarely have one past 20k miles.) Stuff can get pricey at the dealer, our rep gives them to me for free when i ask.

I have heard that walmart has lower tier gas. I find it hard to believe that the bigger stations would sell a diluted product, which in terms hurts their business and bottom line. Greed is greed is though.

My neighbor and a coworker used to fill up at a circle k near our homes, both of their Ram vehicles have had injector replacements and the common denominator was that gas station.
Wal-Mart gas is the same as every other unbranded station.

Comes from BP, Sunoco, Marathon, etc, whatever terminal they pull from.
 

White Eagle

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Did y’all know they sell a diff gas to those inside counties or cities that have the these damn air quality restrictions. That includes the counties Texas big cities are sitting in.

I have a 3mpg milage diff between HEB in Bexar County and Stripes in Real Co or HEB in Uvalde or Hondo.

I DO NOT buy fuel from any place owned by BABOO !
 

Tim. Y.

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I wish the Costcos near me sold Diesel.
 

JTGuy

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I always use 91 Premium gas and have no problems.
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