AlphaWolf

I always use premium but ...
http://www.nytimes.com/2008/08/03/au...o_interstitial

ejsheltra

Saw this too. It makes perfect sense. Only worry is with cars with ECU mod. Tolerances are much more critical to running on premium only.

ohlord

cars are 8-10 years old and high compression,they are referencing cars with new sensors that adjust much more quickly.You take your chances that the old school ecu on a 98-02 w210 can keep up with the load knock and not toast a hole in the pistons.$3 extra 1 tank a week is not worth the risk.Read the caution page in your manual,about how to drive if in an emergency you need to run regular.
in short new car,yes
old car no
ohlord

MB>BMW

93 octane premium/v-power

my baby deserves the best and what it was designed for.

Call me crazy or just in my head, but i feel the difference. IN the rpm range and pull/response from the engine.

AlphaWolf

From the article -
"Nearly all automobiles sold in the United States since the 1990s will happily run on regular-grade 87-octane gasoline without causing engine damage, a benefit of the electronic controls that now manage all engine functions."

Although I won't change, as I don't drive much and gas price does not affect me much, I do think it is okay to use lower grade, but of course performance will suffer and you are taking a chance. But for someone scrimped on cash, that is an alternative.

Ozcan

Well explained Ohlord I would not risk the engine with low octane gas. There were times I had to mix 89 octane with my remaining 93 octane in the tank. But just enough to drive to next station to fill proper octane.

lkchris

If you use regular gas in your Mercedes please post your VIN number here so the rest of us can avoid your car when it comes up for resale.

Ozcan

That was funny!!!

Air Marshall Eldritch

Just had a similar conversation yesterday. A master mechanic with 30 years of MB repair experience. He said he uses premium in all his cars, despite the recommendations (not just the MB). He wouldn't think of using regular.

This after a call came on from a customer driving a brand new S-class who poured Acetone into his gas tank to improve gas mileage on a long trip. He said "we use Acetone to dissolve plastic. Guess what your gas tank is made from?"

People do some crazy things.

ohlord

Note
"Nearly all automobiles" ................Mercedes with over 10:1 compression was not one of them.
Before you would ever hear pinging or knock under load on the m112 or m113 the damage could be done.I just think it is irresponsible journalism by the NYT to make statements that will lead some owners to feed a steady diet of 87 into a jewel of an engine and end up with it going bam.
I have built a ton of engines and build a HC engine with a high stall and light weight and the right cam,you can get away with running lightly on regular.
The Mercedes is not cammed for that operation ,to low a stall,heavy car and high compression a problem waiting to happen especially if you live at sea level up to about 1000 ft. cities.
You won't do it,I know not in Sa with a v8 but if some poor scrimped on cash w210 owner toasts a piston is the author of the nyt article going to reimburse him?

As to the jerks with the acetone and the hho gas and fire from water I gave up on them lost souls
ohlord

Hirnbeiss

That acetone one is a good one. I had an IT employee who swore it gave him another 7-8 MPG on his F150. Urban legends die hard.

I don't think you could damage your car using regular, though. Those of us who grew up in the days of setting our own timing (back in the day) know what detonation is, and cars sure could take a lot of it. In contrast, I've never heard my 1.13 gallon Stuttgarter V8 even start to detonate on mid-grade. Especially here in flat Florida, 93 all the time seems like overkill. Maybe every third tank I'll do 93, that way there's some mixing, but honestly there's no noticeable difference.

I don't think I'd ever use 87, because that's for minivans and four-bangers.

Note however that the quality of gas is determined by more than the octane. I stay with Shell and Chevron/Texaco because they at least pay lip service to clean burning gas (plus I don't like funding ExxonMobil's $1 billion retirement packages).

zx11blade

IKCHRIS you are hilarious!

JamE55

I used to fill up my tank with 91 which you can pretty much get at any gas station in cali but after using 101/109 i'm never going back.

Now i only use a combination of 101/109. Big improvement.

ohlord

you could run 91 in Fl. no problem.

these engines are so well insulated,double walled exhaust manifold and such you will never hear the knock on the door till Dave has already been haued away by the cops
ohlord

Untertürkheim

+1, but you stole my line!

Frugal1

Sheesh . . . when will this nonsense die? Is this the Hyundai forum?

Using a lower octane than recommended may not hurt your car but those computer controls are retarding your timing to prevent engine knock and you will lose performance. Using a higher octane than recommended will not give you any benefit or performance increase or "clean" anything. Those days, if they ever even existed, are long gone.

Hirnbeiss

There is a difference in the quality, but not necessarily the octane, of gas in the US. I thought it was BS when the MB engineers for the M-Class blamed tank level indicator errors on US gasoline, but tests proved it was true.
Find a good supplier and stick with him.
See also:
http://www.shell.us/home/content/usa...e_experts.html

Musikmann

The MB recommended 91 octane is unavailable here. The few stations of which I am aware offering 92 contain ethanol. I use Chevron Supreme 93 because that is a Top Tier Gasoline, has no ethanol, and Techron Concentrate is approved by MB. The cleaning properties are due to the detergent components, not the octane.

ohlord

that danged ethanol
10% added to arco gas out west and even though the gas is pennies cheaper it will trip a p0170 p0173 maf code at times that will drive you batty chasing it down.

Ozcan

Ethanol is everywhere.
I used to live in Florida and they had 10% ethanol mixture.
I moved back to DC area and they have same ethanol mixture here too. Also the states I drove thru all had ethanol.

ohlord

a conspiracy to keep the w210's drunk all the time so they forget to get their trans fluid replaced
ohlord

lkchris

Because it's Federal law. Pork for farmers. No requirement to label pumps, either.

As to the subject of this forum, addition of ethanol does not degrade octane. About the only good thing you can say about it.

01BlackE320

Around here right now, premium 93 octane Sonoco is $4.39. 91 Octane is $4.34 so I save 5c a gallon using 91. The Sonoco station sells 4 grades. The one time I put regular in by mistake, definately heard the engine knock. 91 octane is what it calls for and what I use. Don't notice any difference between 91 and 93 so I keep the nickel in my pocket.

Musikmann

The laws must be state-by-state and not federal because we have one that requires a label pump if the gas contains ethanol. West Virginia is pretty backward in a lot of ways, but this is one area where we seem to lead the pack.

GGM

Florida also requires a label. Saw them in Georgia, too, this summer.