WTF...Gas mileage suddenly drops from 16 to 9??

Please don't shoot me if this is a duplicate...I *think* I've searched deep enough...

I have a stock '01 Sport with CA emissions. I fuel up in Toledo, OH and drive out the tank mostly on freeways, averaging 16 mpg (I know that's a bit low for stock, but I'm fully loaded and have a bunch of stuff up on the roof).

Then I fill up in Sandusky, OH and drive down to Columbus -- suddenly averaging 9 (yes, NINE) mpg. There's no loss of power, no new (or absent) noises...everything seems the same except gas mileage. The one thing I did notice is a little more heat than usual on the floor near my right foot.

Any ideas? Is there a chance that Sunoco gas is really THAT bad, enough to cut my gas mileage almost in half?? Anyone ever seen anything like this? Any advice would be appreciated...at $3/gal, 9mpg is gonna put an end to my travels toot sweet...

I'd question the gas before questioning the vehicle. try another tank from a station you trust, if that doesn't work start considering a problem with the vehicle.

Did your rpm change when your mileage went down hill? More heat than usual by your right foot sounds like either your trans is getting hotter due to slippage or binding, or a hotter than usual exhaust. Since it's an 01 with the cats close to the exhaust manifold you may have a cat clogging up causing excess heat build up. Or you may have an excessive amount of fuel going to the engine, that's still burning in the exhaust. Any black smoke coming out the tailpipe? Alot of hillclimbing? I had always heard of Sunoco gas being better, and creating more power, but that's from reading magazines. But as the previous post says, give it another tank.

Living in central Ohio, Columbus, I can tell you we're the dumping ground for bad gas and diesel. Sunoco is owned by BP. They have been known for crappy gas way back in the Sohio days. Also Alcohol cuts your mileage down by about the same percentage as the blend. (10% alcohol, 10% drop in mileage). It's realy very hard to get a tank of good fuel around here. I'm not too sure about northern Ohio but my son getts better mileage from his diesel jetta when he tanks up in the Toledo area.
JoBo

JoBo said:

Living in central Ohio, Columbus, I can tell you we're the dumping ground for bad gas and diesel. Sunoco is owned by BP. They have been known for crappy gas way back in the Sohio days. Also Alcohol cuts your mileage down by about the same percentage as the blend. (10% alcohol, 10% drop in mileage). It's realy very hard to get a tank of good fuel around here. I'm not too sure about northern Ohio but my son getts better mileage from his diesel jetta when he tanks up in the Toledo area.
JoBo

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2X that Ohio is one of the few states that has no fuel testing.Most long haul truckers will tell you don't fuel up in Ohio if you can help it.

We've had a couple of gas stations here in PA in the news this past couple of weeks who had gotten and were selling bad gas, bad enough to stop the vehicles that bought it within 20 seconds of startup.
I know it may sound kind of funny but sniff your gas tank filler, does it smell funny ? does it have a varnishy type smell ? if so thats bad gas, old gas actually.

Take a look at a plug, if it´s coated in red, it may be watered gas. High humidity will do it also. Pretty darned common, they put in X amount of water, then alcohol to help keep the water in suspension (sometimes they even skimp on the alcohol). But if it reaches a critical point, the spark breaks down and the plugs turn sooty. If it gets really bad, you pick up a terrible miss.
Seems to be more common at Mom and Pop stations, were another hundred bucks here and there really adds up.
Can be other things, but the price of gas being what it is, the temptation is there for the refiners and station owners.
I usually put in a dose of injector cleaner or gas tank anti-freeze, helps keep the water from settling to the bottom and causing real problems.
I usually buy gas at a high traffic station (chain run), that´s not too far and not too close to the interstate. Far enough they compete with price, but close enough they have a pretty good turnover in stock.
Change of season, it seems to get worse, I think they forget to figure in what they pick up from condensation in the tanks, when watering there stuff or maybe it´s shortly before they switch to winter blend.
A good project for 5-90 would be to find some moisture absorbing silicate or something, that gas won´t dissolve, that changes color according to the amount of water absorbed. It might be a big seller in the right circles. In my diesels, I´ve walked into a station with a glass jar a quarter full of water, three guarters full of diesel and my bills for the last half year. Makes them really nervous. Doesn´t really prove anything, but it´s good for a laugh.
Could be some sensor and/or sensor connector is bad and your running really rich. It will sure enough heat up the cat.

I think that dye is used in untaxed diesel.

noresttill said:

I think that dye is used in untaxed diesel.

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No this stuff is gray in color and comes in pellets or paste. Drop a pellet into a gas sample and it turns bright Purple, the paste is used on the end of the dipstick used to check the fuel level in under ground tanks.

langer1 said:

No this stuff is gray in color and comes in pellets or paste. Drop a pellet into a gas sample and it turns bright Purple, the paste is used on the end of the dipstick used to check the fuel level in under ground tanks.

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Having worked at a Sohio station many years ago I can tell you the paste on the stick is to see how much or if there is water is in the tank. The level of the gas can be seen without anything being put on it, one side of the stick was flat black and where it is wet with gas it's glossy. A tank truck driver once told me to never buy fuel where the tank truck is unloading. The reason is there's water and dirt in all tanks and it normally sits on the bottom. But with thousands of gallons dumped into it causes it all to get mixed up.


JoBo

Update: OK, looks like it was indeed a tank of bad gas. Fueled up at BP in Columbus and MPGs went back up to 15-16. Phew... Thanks for all the advice!