[dholter65]

Had my car in for service at BMW today for regular maintenance. Mentioned that my car feels like its running a hair rougher than usual last couple months. Everything they inspected looked fine so they decided to run a fuel quality test & my last 5 refuels came back at 1 quality rating out of 3. (1 is essentially rated as regular fuel, 2 is mid grade & 3 is premium).

I know for a fact I always put premium into my car. I'm usually super specific about going to a quality station like Shell, but the last couple months I've moved and had a Fry's (Arizona) very close by to my house & began filling up there as the Shell is out of the way.

Pretty concerning that I'm expecting/paying for premium fuel and getting something that's comparable to 87 that I've been running in my M5.

[jnotrom711]

im in AZ also, and I only fill up at the thumb in N Scottsdale with 95 or a mix of 95 and 91 octane just to be safe, since I have a racechip. Not sure if it even matters but I feel like I can feel a diff. They also sell 100 octane if you want also. In the pumps nothing special you need to do to get it.

[dholter65]

Good to know for sure, appreciate it. Was definitely in shock when all the premium fill ups were coming back as regular grade quality.

[Ex_Stig]

I ran my M5 CS on gas from Costco in North Scottsdale for 2 years. Never had a single issue. Before that I ran my stage 1 M3 CS the same way.

Did your dealership charge you for the fuel analysis?

[AHall]

This is quite unfortunate. How were they able to perform an analysis of the previous four tanks of gas? I am curious how this happens as there must be several safeguards in place, color codes, what did the gas station order, how much tank space was available in the premium tank, what was the cost to the station for a tank of regular vs premium gas.

I have heard of gas stations even putting diesel in regular gas tanks. Really surprised at the number of process failures or lack of safeguards.

[logicators]

Originally Posted by Ex_Stig

I ran my M5 CS on gas from Costco in North Scottsdale for 2 years. Never had a single issue. Before that I ran my stage 1 M3 CS the same way.

Did your dealership charge you for the fuel analysis?

Same here. Costco is great, their gas is top-tier rated and they tend to do a good job with quality control across their products. I have used their premium gas for 10+ years in cars that needed it (including my M5C) without any issues.

[dholter65]

Originally Posted by Ex_Stig

I ran my M5 CS on gas from Costco in North Scottsdale for 2 years. Never had a single issue. Before that I ran my stage 1 M3 CS the same way.

Did your dealership charge you for the fuel analysis?

Nope, no charge.

[dholter65]

Originally Posted by AHall

This is quite unfortunate. How were they able to perform an analysis of the previous four tanks of gas? I am curious how this happens as there must be several safeguards in place, color codes, what did the gas station order, how much tank space was available in the premium tank, what was the cost to the station for a tank of regular vs premium gas.

I have heard of gas stations even putting diesel in regular gas tanks. Really surprised at the number of process failures or lack of safeguards.

I think it's tracked in the vehicle. They could see my last 5 refuels & what mileage those were at, and they could literally see the lifetime of the vehicles' fill ups and the quality of gas from each fill up.

[Ex_Stig]

Ask them to check another M5 next time it’s in for service. Will be interesting to see the difference.

[Greer]

Only Shell V Power in my M5, but I will check the fuel the next time I am in for service.

[dholter65]

The print out from their system calls it "Fuel Grade Recognition"

[NoMods]

I use Costco 99% of the time, 1% is Shell

[IAmSpeed]

I only go to either Costco or Shell, zero issues in 10+ year!

[M5_508]

I always use Shell’s V Power. That’s what is recommended at least on gas cap.

[asif163]

Same thing happened to me- I always filled up at the local BP w/93 and my fuel read came up saying it was non-premium. I think BMW can diagnose at least the last 90 days worth of fuel readouts. Started using another station after that!

[micvite]

Originally Posted by dholter65

The print out from their system calls it "Fuel Grade Recognition"

Here's the thing though... you got the scale wrong... grade 3 means 94 and above octane (98 in europe) because it's actually 93.5 US so you can get lucky with some 93 fills that are slightly better and get you a grade 3 reading. Grade 2 is 91- 93 us while grade 1 is really 91 and below (grade 2 is 95-98 ron, grade 1 is below 95 ron) so not necessarily regular, but iirc Arizona has mostly 91 as their premium fuel. In NJ we have 94 at the sunocco pump and that gives a grade 3 reading instead of 93 usually being grade 2.

[Maverik259]

ya i used to get Sams Club in my X5 because it was so cheap back when the gas prices first initially skyrocketed. but then when i read about the different tiers of gas stations and why some can be so cheap i immediately stopped and only go to mobil/exxon for my x5 and m5. would use shell too but its no where near here i live. Have also heard good things about costco but again only 1 in the vicinity and its not near my house or work.

would love to have the dealer run a fuel diagnostic just out of curiosity to see how my local station is doing. haha 93 here in VA.

[Ex_Stig]

Originally Posted by micvite

Here's the thing though... you got the scale wrong... grade 3 means 94 and above octane (98 in europe) because it's actually 93.5 US so you can get lucky with some 93 fills that are slightly better and get you a grade 3 reading. Grade 2 is 91- 93 us while grade 1 is really 91 and below (grade 2 is 95-98 ron, grade 1 is below 95 ron) so not necessarily regular, but iirc Arizona has mostly 91 as their premium fuel. In NJ we have 94 at the sunocco pump and that gives a grade 3 reading instead of 93 usually being grade 2.

You sir are correct about AZ. Hard to find anything over 91 without spending significant money.

[micvite]

Originally Posted by Maverik259

ya i used to get Sams Club in my X5 because it was so cheap back when the gas prices first initially skyrocketed. but then when i read about the different tiers of gas stations and why some can be so cheap i immediately stopped and only go to mobil/exxon for my x5 and m5. would use shell too but its no where near here i live. Have also heard good things about costco but again only 1 in the vicinity and its not near my house or work.

would love to have the dealer run a fuel diagnostic just out of curiosity to see how my local station is doing. haha 93 here in VA.

Should show up at a tier 2 fill, if you're lucky (because us gas is minimum octane rating and it's over 93 the one day you're at the pump) you might have a few tier 1 fills.