Think you were given bad gasoline? It's not so easy to prove

As Clarence Davis prepared to fill up at a Bedford gas station in August, he noticed a tanker truck nearby refilling the tank. He bought gas anyway.

Immediately afterward, he says, his car's engine sputtered and died. He took it to a repair shop and was told he had purchased gas that probably contained water.

He went back to the station outside a Kroger on Harwood Road and filed a complaint. He also filed one with the Texas Department of Agriculture.

Kroger looked into his complaint. The store regularly checks its gas tanks for contamination. All tests showed the gas was fine. A state inspector from the Agriculture Department showed up the next day. The inspector did an on-site test and also sent the fuel to a lab. State officials determined that the gas in the tank met proper standards.

The Euless man got his car repaired for $500. The mechanic gave him a milk jug filled with a sample of the supposedly bad gas.

This month, Davis took Kroger to small-claims court. He carried a sheaf of papers showing what he had gone through since the August incident. He brought the milk jug, too.

Davis asked a jury at the Hurst subcourthouse to award him $700 for repairs and expenses.

Kroger mounted a strong defense. The store manager testified that employees test the gas tanks throughout the day. The manager also explained how gas pumps have filters that automatically shut down if bad gas tries to pass through. The manager also testified that no other customers had complained.

For his part, Davis told his story and showed the jury his milk jug.

That jug proved to be his undoing.

The only proof he had that it contained bad gas was a notation on his repair bill by the mechanic -- "Found vehicle with contaminated fuel." That was one mechanic's opinion -- it wasn't proof.

After five minutes of deliberation, the jury found in favor of Kroger.

What I've learned is that in small-claims court, it often takes that extra step of research. What should people do when they believe they've bought bad gas and have a costly repair bill?

Turns out that Davis did many things right. But he could've gotten the fuel tested, to try to confirm the mechanic's opinion.

He quickly contacted the store to complain. He was correct to get the car mechanic to give a diagnosis in writing, and he was smart to immediately call the Agriculture Department and file a complaint.

So how do you get fuel tested? The Watchdog spent two days trying to find a lab that would even answer questions about it. I learned that petroleum testing labs work for the major energy companies and aren't that interested in helping a consumer test a milk jug of gas.

I did find a lab in our own back yard. Armstrong Forensic Laboratory in Arlington tests gasoline, usually for insurance companies in response to claims by customers such as Davis. (Davis didn't file an insurance claim.)

Here's the bad news: Lab owner Richard Armstrong says the cost to test Davis' milk jug would be about $300. Add the $100 or so to file the small-claims lawsuit, and that's $400 spent to get the $700 Davis was seeking. It becomes cost-prohibitive.

If you're worried about getting contaminated gas, keep these things in mind.

First, you should know that the chances of getting bad gas are very small because of the extensive testing system along the pipeline from refineries to pumps, said Patrick Kelly of the American Petroleum Institute.

But some will advise that you avoid buying gas when a tanker truck is doing a simultaneous refill.

"Gasoline is lighter than water," explains Phil Sorurbakhsh, co-owner of Texas OilTech Labs in Houston. "So all the sediments and the water are on the bottom of the tank. With rain, every time the tank is opened up, humidity starts to accumulate, and it ends up in the bottom."

When a tank is refilled, he said, "it stirs things up, and you may get some of that in your tank. It has a higher probability, let's put it that way."

Others advise that you get a second mechanic's opinion.

Armstrong, who has tested gas for insurers, warns, "Lots of unscrupulous garages say it's bad gas when it's a bad filter or this or that. The gas delivery system is pretty clean, actually."

Clarence Davis says it was scary standing up in that courtroom and presenting his case. He did a good job, but he was missing that one crucial element required -- scientific proof. Turns out that's difficult and expensive to come by. Ever since, he says, when he sees a gas tanker filling a tank, he skips that pump.

The Watchdog column appears Fridays and Sundays.

Dave Lieber, 817-390-7043

Twitter @DaveLieber