Good gas / bad gas, how do you know?

Here’s a product idea someone in here can make a mint from, unless it’s already out there somewhere.

This forum is loaded with driveability concerns related to fueling up with ‘bad gas’ and I myself have often wondered…

How can anyone know BEFORE they end up with an entire tank full of junk ?

How about a test strip similar to the PH and antifreeze test strips ?

Something that a person could hold right in the flow of gas at the tip of the nozzle as you begin to fuel up.

- Squeeze the trigger for just a spit while you hold the test strip in the flow.

- stop and check the reading to know if you’re getting good gas.

- if not , pay your 50 cents and leave.

We’ve been selling fuel pumps right and left for the last couple of weeks. There’s bad gas in this town somewhere, but how can Joe Customer avoid the $500.00 bill ?

Is there a product like this out there ?

Could there be with a little tweaking of existing chemical test strips ?

What do you mean by bad gas? Old gas? Gas that has water in it? Gas that has particulate contaminates?


YES :wink:

all of the above.
Joe Customer sticks that fuel nozzle in his filler neck and squeezes the handle…
on a wing and a prayer.

Wrong octane ?
too high alcohol content ?
sediment ? water ?

Here at my Ford dealer we see some awful crap in these tanks when replacing fuel pumps which we show to the customer before cleaning it out and advise them to buy from reputable stations.
ALL these customers have a valid point when the throw up their hands perplexed " How the h-- am I supposed to know, taste it ?"

There’s an assumption around town that there’s too much winter mix gas still in inventory that have sent dozens of trucks to the local shops for fuel pumps.
Yet these tanks seem to all have a lot of sedimentary junk in there with no common denominator in where they bought their fuel.

I don’t think that Joe Customer would be able to do a complete gas analysis on the spot prior to filling the tank.

But what should be done is, the gas pump should do this job. The technology is there so if anything out of the ordinary is detected in the gas, the gas pump automatically shuts off. But who’s going to do that?


The gas at most stations all comes from the same distribution center. BP may supply one area and Gulf another and a third is an independent distributor who buys it from the other two. There may be different additives added at the different brand stations, or not.

I have heard time and time again, about how bad gas caused this or that problem. Not really likely. The wrong gas (wrong octane for your car) can be a problem, but bad gas is not the problem most people think.

In over 40 years of driving, I have had fuel twice. Both cases was a result of water due to a problem at the specific station. (one diesel the other gasoline.

Real problems due to bad fuel is really rare.

I don’t think you would want a strip (even if small) with gasoline vapors on it, being thrown around as station parking lots. The problem is not about the gasoline color, or something which can be measured by a litmus strip.

The method of determining the quality of the gas is to take a small sample, and heat it up in a cup under pressure, and see what temp it explodes at. called “closed cup” testing. when hauling a load of gas from the refinery to a local distributor the only way octane is checked is by the specific gravity of the product. each load (i’m talking about 4 million gallons at a whack here) is tracked arrival and departure to make sure the specific gravity is the same. They know if the product has been changed (by introduction of other grades) if the specific gravity changes. Each load, and variety has a different specific gravity. I know, not very scientific, but it is what they use. The color is an indication of purity too. Frequent samples are taken to ensure uniformity during the transfer process.

I feel the intermediate delivery is where tanks get messed up. The big name oil companies use specific trucks for delivery of gas, and others for diesel. I know (have seen) independent drivers and companies use the same truck to haul diesel, then gas, then slop waste oil, then return to gas. So I KNOW it happens. Even though your average truck driver swears the truck is M/T there is always sludge/residue left from the previous load. I’m not saying the contamination comes from trucking, but it is certainly a part of it. I haul petroleum in 4.2 million gallon lots. If there is residue or sediment left it is at such a small percentage that it is unnoticed/able. however when put into a 2500 gallon tank contamination IS noticed.

The problem is improper ethanol blends, and to a larger extent the sediment and crud from the tanks (both the supply and the station.) The ethanol mixture is blended locally at local distributors. If they don’t get it correct, cars that ae supposed to have E-15 are getting E-20, -30- etc. Fuel pumps that are dying are monst likely dying from ethanol, not crud. I personally only buy gas a stations which are clean, and well maintained (on the outside) I figure that if a station can’t be bothered to keep the outside clean, how can you depend on them to change the filters that are mounted on the pumps themselves?!
also, in the last 5 years or so, the refineries have been selling ( or should i say the oil sellers are purchasing!) a different (lower) grade gasoline. this is called ‘hard cut reformate’. This is used to “stretch” the gas, thus making ‘more’ gas, out of lower quality fuel. this is similar to adding ethanol, except it is not done to boost octane, but to simply boost revenue, by ‘making’ more product.

put seafoam in the tank if it is bad it will help

That’s an interesting possibility but I could see a couple of drawbacks.
One is that any litmus paper wouldn’t detect solid particulates.
Two (and just my personal opinion here) is that the vast majority of the motoring public will simply not want to be bothered with doing this test. It’s far easier to stick the nozzle in the filler neck with no thought of bad gas until when or if the car quits.

As to gasoline contaminated by water or solvents, etc. I think this does happen on very rare occasions but the vast majority of pump failures are due to solid particulant clogged filters. If the filters were changed on a regular basis odds are the number of pump failures would decrease quite a bit.