Techron = Placebo Effect?

[gmercoleza]

Whenever I heard someone say they got a bad tank of gas, or told someone to avoid a certain gas station or chain because they sell bad gas, I thought it was all in their head. In all my time driving, I have NEVER experienced anything resembling a tank of bad gas. That is, until a few days ago. I filled up at Wal-Mart / Murphy USA and immediately after filling up - and I do mean IMMEDIATELY - my car started doing this weird jerk. As I was pulling out of the station, it seemed like it was either misfiring or shuddering, just once here and there, but each time it occurred it shook the whole car. It kept doing it intermittently throughout my lunch hour. It wasn't really noticeable at speed i.e. while moving; it only seemed to occur while stopped at a light with the trans in drive. As the day progressed, and through my hourlong commute home, it went from intermittent to being regular. At that point, stopped at a light, the car would "jerk" about every 20 seconds or so. Each time it jerked, it felt like a really bad misfire, as if the engine was going to cut out. But it never did. Boy did it make me nervous though.

The next morning, I was backing out of the garage as usual. I normally start the car right up, put it in reverse, back out of the garage, and then idle for a few seconds to let the engine warm up. Our 20 x 20 master suite is above the garage, and I don't like the thought of gassing my wife as she sleeps, so I idle outside the garage before leaving. Except this time it stalled when put into reverse. I put it back in park and cranked, and nothing. Had to crank and crank and crank and then it finally caught, but very weakly. This was scary now. I let the car warm up for about 5 minutes and, having no choice, drove it to work. Once again, a nerve-wracking commute as the car kept shuddering and misfiring, leaving me to wonder when it was going to stall on me. But again, it never did this at speed - only while sitting stopped with the trans in drive.

After a few days of putting up with this, I put two and two together and decided that maybe it was in fact the recent tank of gas causing the problem. Did some research on this board in the past and had read a lot about Techron, so I took a chance, picked some up yesterday at lunchtime with about 1/8 to 1/4 remaining in my tank. Dumped the whole bottle in there, then put $10 of gas in (about 4.5 to 5 gallons). Then I proceeded to drive it like a Formula One car, very hard. Throughout my lunch hour, it still did the same stumble/misfire thing. But here's where things get interesting. On my drive home, although it continued to jerk, it did it a little less. By the time I got home, it was jerking only about once every minute or two when stopped at a light. And the jerks weren't as severe.

When I got home after work, I put the wife and kids in the car (rather than use the minivan) and we drove it to get some things done. Through the drive, the jerking kept decreasing in frequency and intensity. By the time we got back home, the car seemed to be *mostly* back to normal. I say mostly because the jerking was gone completely, but the car seemed to idle slightly rough, whereas it used to be pretty smooth. On a scale of 1 to 10, it used to idle at about a 9, but now it was about a 7.

Driving to work this morning, same story. Idling at about 7 to 8 (not perfectly smooth), but no stalling, jerking, or misfiring. The few gallons with the Techron in them are almost entirely burned up, and I will have to fill up again once I get home.

Here are the questions I have:

1) Do you think my problem was caused by bad gas?
2) The tanker was filling the station up when I was there. I've heard theories that this is a bad time to fill up since it stirs up impurities in the underground tanks. Is there any truth to this?
3) Did the Techron actually cure my problem or was it coincidence since I had mostly burned off the "bad" tank of gas?
4) Do you think this was just a freak thing and is gone, or will the problem come back?
5) I have filled up at the same station here by my workplace for nearly a year and have never had a bad experience. The few gallons I put in for the Techron came from this same station, and I plan to continue using the same station unless this problem occurs again. Am I stupid?

Thanks everyone.