Update on my cold start studdering problem - problem fixed?

Hi all, I have to guess it was just bad gas. Betsy would sputter on startup but after a few seconds, it would be fine. I filled up at small town Citgo station in northern Indiana and for the week after that the sputtering was a problem. This weekend, though, I bought new gas, and she started fine on Sunday and this morning. I'm chalking it up to bad gas, or maybe water in the gas? I also wondered if even though I chose premium, that they sold me a lower octane by mistake?? My father mentioned that he has seen in the news when sometimes stupid gas truckers will fill the wrong tanks with the wrong octanes.... I'll keep an eye on it, and avoid this particular station near my wife's in law's home in the future too.<br>

...since water is denser it will settle at the bottom of the tank, possibly near where the pickup /feed line is. Once you drive a little the sloshing of fuel in the tank would disperse any water through the rest of the tank. Have no idea though how the SLK gas tank is shaped and where exactly the pickup/feed line is located.<br>
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Lower octane gas shouldn't cause a sputter, but it may cause engine knock/pre-ignition.<br>
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Hey, maybe the bad-gas station could be an excuse not to visit the mother-in-law? I never thought of that one... :-

Did you fill up the tank at the gas station in question? If so, it could be that the gas wasn't bad but the auto shutoff on the pump was bad and you overfilled the tank and got gas in the fuel vapor recovery system. Just a thought, but either way, you should avoid the station.

Now that you mention it Brian - I did fill it up, usually trusting the gas pump to shutoff when the tank nears full. I've never bought gas at this station with my SLK before, though I have with my wife's 1995 Oldsmobile Cutlass Supreme 4door dozens of time. But of course, the Olds takes 87 octane, and the SLK takes 92 octane. <br>
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I am now leaning towards your suggestion of the overfill/vapor recovery system. Someone else on this board suggested that to me also, and my father-in-law who owned a gas station years ago also suggested that could have been the problem. Thanks all - I hope there was no permanent damage. 'Betsy' is running fine now - in fact, great!<br>
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It's going to be a BEAUTIFUL weekend here in Indianapolis. I can't wait to get out and about...<br>