How can you tell if you have bad gasoline?

Answer by  lovelife (998)

If you have bad gasoline, the engine may sputter out and die or it may cause other performance problems. It can cause misfires and you may notice your "check engine" light come on. It can be caused from dirty gas, poor gasoline quality or from your own car having a dirty filter. Take to your auto mechanic for a check-up.

Answer by  technogeek (6640)

If your car starts running badly or your gas mileage starts to slip, then you probably are using bad gas.

Answer by  Advisor (1032)

Luckily, this is not a hard problem to diagnose. Usually within a few miles (depending on how much "good" gas you already had in the tank), tainted gasoline will cause your engine to sputter and the car seems to miss or be out of tune.

Answer by  Darrell (316)

When you have bad gas in your car, it will generally start running rougher then it normally does. You may also find your car seems to sputter, experience a loss of its usual power and may even start to die when idling.

Answer by  Amber40 (24961)

If it has set for awhile you can bet it is probably bad. Really the best way to tell is to take some and light it on fire. If it won't light or is hard to light it is bad. Just drain your tank or add some fresh high octane to it.