I always use Costco gas. It is significantly cheaper and there are millions of other people who use it in their much higher performance cars than GTI's without issue. If your mpg dropped 5 mpg there is definitely a different factor than the gas. There is no way that you would lose that much because of the gas type. Shell and Chevron use marketing tactics to trick you into paying their higher prices. Its not better gas. The only places you need to watch out for are the no-name non-chain stations.
7
Costco vs shell gas
- Thread starter dtran11
- Start date
Strange Mud
Autocross Champion
- Location
- Small Town CT
- Car(s)
- Assorted
not sure I completely agree with Jim. I'm confident well over 1/2 the people that aren't car folks could not tell you what Top Tier gas really is. I also think that over 1/2 of the gas sold that isn't designated Top Tier (and I do know what that is) would pass Top Tier muster but the seller just doesn't want to pay the extra $ to have the designation. No facts just gut feeling.
but then I run regular so I'm already suspect...lately from the Citgo (Top Tier) station in town that opened 6 months ago and started a price war with my small town going from having gas that cost .10-20 more per gallon than surrounding towns to one that now has lower than average prices
Mud
but then I run regular so I'm already suspect...lately from the Citgo (Top Tier) station in town that opened 6 months ago and started a price war with my small town going from having gas that cost .10-20 more per gallon than surrounding towns to one that now has lower than average prices
Mud
KevinC
Autocross Champion
- Car(s)
- '19 Golf R, '21 M2c
So are you actually aware of any non-Top Tier brands that meet the top tier additive requirements, even though they are not "certified" as such? Would love to know what those are - if any actually exist.
tigeo
Autocross Champion
- Location
- Richmond, VA area
Costco has great gas. Top Tier. I use it all the time and I am tuned etc. Any variation you saw is simply based on normal variability. One tank tells you zero. I have collected mpg data for over 30K miles using Fuelly. The biggest trend I see in my data is after I got the IS20 which definately impacted my "sending it" - a whopping ~0.5mpg ding in my overall mpgs best I can tell from the trendline on the graph. My average with Costco over 81 fill-ups and 50%/50% city/hwy split = 23.9 mpg. My average with Shell over 24 fill-ups and 63%/37% city/hwy split = 22.6 mpg. My average with Exxon over 21 fill-ups and 34%/66% city/hwy split = 24.9 mpg. All makes good sense.
NopeR
Autocross Champion
- Car(s)
- 18 Golf R
Petro
Are you using the 94? My MPG on 94 is straight garbage lol.
jimlloyd40
Autocross Champion
- Location
- Phoenix
- Car(s)
- 2018 SE DSG
Quite possibly you're correct but what does it cost to get the designation?
NopeR
Autocross Champion
- Car(s)
- 18 Golf R
Petro 91 or 94 makes no actual difference in mpg on my end. Neither does shell 91 for that matter. Driving habits have an impact over what gas is used overall. This all comes down to personal preference.
A little lube always helps get the tip in.
pitterchi
Ready to race!
- Location
- Northern VA
I haven't filled my tank since the Pandemic started "work from home" but I don't see that much of a difference between Shell and Costco. Shell does feel a little better in my car but I'm not sure if the computer is adjusted to Shell already. Personally, the distance and the crazy long lines at Costco prevents me from using it regularly and even though the savings is pretty significant per gallon, its a few dollars per tank.
VW recommends top tier fuels and thats what I try to put in.
But maybe give it a few tanks before making a decision? Maybe pull the ground off your battery for 10 min to reset the ECU and see if it improves? Kinda tossing things out and i know its a reach but its possible.
I agree with those saying gas is gas but I do favor Shell over others.
VW recommends top tier fuels and thats what I try to put in.
But maybe give it a few tanks before making a decision? Maybe pull the ground off your battery for 10 min to reset the ECU and see if it improves? Kinda tossing things out and i know its a reach but its possible.
I agree with those saying gas is gas but I do favor Shell over others.
Golfs everyday
Autocross Newbie
- Location
- USA
I've been pumping both regular and premium from my local Mobil station a few blocks away for my various cars to support the store. I cannot tell the difference between Shell and Mobil. For cars that run 93 octane, I never pump at discount stations as most in my area do not offer 93 octane.. they only go up to 91 or 92 at best.
I've never had a problem with regular gas at discount gas stations.
On another note, I've been running gas stabilizer in the tanks since the pandemic as gas can spoil if left in the tank too long.
I've never had a problem with regular gas at discount gas stations.
On another note, I've been running gas stabilizer in the tanks since the pandemic as gas can spoil if left in the tank too long.
tigeo
Autocross Champion
- Location
- Richmond, VA area
The notion that your car needs all this time/several tanks to adjust is false. You put gas in, your ECU adjusts timing if necessary based on the knock sensors. That's all there is to it. It's instantaneous, it's not AI.
I'm pretty sure my car is plotting to enslave mankind, so.........