This is one of those threads that could go on forever...

All I know is that when I try a lower grade gas, I hear pinging/knocking.

pinging/knocking=not good

:rolleyes:

...and if you hear pinging you have at least one defective knock sensor...

Low octane numbers ?
 

Beav, I find it hard to believe that in the land of a million petrol pumps that the octane numbers are so low. Here in Aust. the lowest ULP is 92, the premium is 95 and there is OPTAMAX which is 98RON.
The sticker under the hood of my 95 mod says minimum octane 95RON.

When I am doing a fast trip out west, I use 98RON, you can feel the difference when overtaking at around the 200kph(120mph), the top end is much stronger. The computer lets the ignition advance, to develop the max pressure and torque.
I bet it really drops it's bundle when running on 80 RON.
Wouldn't pull a greasey stick out of a pigs arse!
:D :D
Harvey.

Before this becomes overblown (it hasn't, has it? ;) ) I wasn't recommending to use regular exclusively, but saying that it was ok periodically. In fact, I just read today in the Subaru TSBs that very same statement.


Around here the prices fluctuate daily, if not hourly, and I see no reason to pay exorbitant amounts just so the distributor can buy a new house next week. I'm lucky that there's a station at the end of our shop and when they get "the call" to raise prices they let us know to gas up before the jump. Sometimes the jump is 28 cents - close to a 25% increase in less than a minute. I know I don't speak for everyone (obviously... *S*) but I see no reason to spend money for the sake of someone else's interests. I can weather a few tanks of regular now and then.

I mean, geeez, I haven't noticed any handles around here that end in Foyt, Unser, Lauda, Andretti, etc...:)

Beav

If we all liked the same things we'd be standing in a helluva long line...

Re: Low octane numbers ?
 

Hey Harvey, isn't RON a different designation than we Yanks & others use to denote octane? I think 98RON (whatever that stands for) is equal our 93 octane premium. It's sorta Pounds vs. Dollars.

Beav - just to continue beating the dead horse, I've always filled up 40 years worth of vehicles with whatever octane the manual called for, but usually the cheapest off-brand crap I could find, since I truly believe it's all the same anyway. I thought the rule was to just buy from a high volume dealer because of less possibility of water contamination. Whatever, the "real" answer is, I've never had a problem with fuel related repairs in a whole bunch of vehicles for a whole lotta' years.
Ron (not RON)

I see a few more cars than most people ;) , fuel pumps in injected cars has become a quite common repair - usually around $350 - $500. #1 culprit - contamination.

Sad part is that even if the mechanic flushes the tank when changing the pump it's up to the customer and their choice of stations to fill the car with clean fuel. Most continue to use the same cheap crap from the same station(s) that probably caused the problem in the first place (not to mention the people that drive around without gas caps...) Same crappy gas + same contamination problem + new fuel pump = warranty replacement. Actually as a result of so many warranty claims, the manufacturers of the pumps are trying to talk auto manufacturers into making the fuel pump and the gas tank a sealed unit (If I remember correctly there's one or two models that have these now.) That way it will be easily evident that the pump failed from new contamination and the warranty will be voided. Everyone is going to love the price of those bad boys, figure average price around a grand. And you can thank those people that can't see the light when it's your turn to step up to the plate.

Let me head the next logical question off at the pass: no the in-tank sock filter doesn't protect you from contamination. It does work for 30 micron boulders, but even enough of those will plug or restrict the sock enough that the pump doesn't get a nice clean flow of fuel. Without that nice flow of fuel the pump overheats - yes, the fuel is the coolant for the pump. The stuff smaller than 30 microns (just grabbing a reasonable number here) pass through the sock and end up you know where, causing the pump to fail.

There's really no hard and fast rule about where to buy your fuel. I guess the thing to do is try to buy from a high volume dealer. They normally keep their tanks full, are more likely to buy from distributors that have their own trucks. Contracted haulers may carry other products that leave contamination in the tank. Old gas stations have more chances of 'old tank' contamination. I do agree that in a given area name brand and local brand stations probably buy their fuel from the same supplier(s). Everywhere I've lived the prices are usually within a few pennies so that was never cause for me to go to unknown brands.

Have a great T-day!

Beav

Beav, excellent information. If I may add one note: NEVER, NEVER, NEVER fill up at a station when the truck is filling up the tanks or you see the truck pull out when you're pulling in. This is one of those "common sense" things that passes us by, but, when the truck is filling the tanks, it is stirring any sediment in the bottom of the tanks. It's best to wait for those sediments to settle down before filling your tank.

regular gas
 

Just bought a 97 SVX (26K) to add to my soon to be retired 92 SVX (138K). The Toyota dealer changed the oil (only 5 quarts) and filled the tank (must have been regular). On the way home (200 miles) it shuddered and I had a cylinder misfire that tripped the engine warning light. One can of fuel system cleaner, one can of octane booster, and a new tank of premium and all is well. PREMIUM ONLY!!

I have about 95k on my car now. Since I got the car (75k), only once, I had put 87. In IL, I can only get 87, 89 and 93. I have talked to the dealer and he recommended I combine 89+93 to get 91 -- nice logic (89+93)/2 = 91. But I have always dumped in no lower than 92. Even at 92, I can see my gas mileage decrease -- who is counting anyway :D

at 92, full tank till the light comes on, I get around 300 miles
at 93, full tank till the light comes on, I get around 350.

There is the difference and for that extra buck or so you pay at the next gas station, it's well worth that extra 50 miles plus knowing that you are putting better gas. Once in a blue moon, I put in the NOS octane booster -- just to see the performance increase for a bit.

Lwin