So I have a 2000 Honda Civic LX that is around 130k miles now. In Las Vegas, I put E10 (I hadn't known what it was before this...), and had to get it fixed. The engine light had started blinking and my car had started shaking (similarly to how it would feel when the cylinders mis-fire) in less than 2 minutes of driving the car.

The mechanic in LV cleaned out the fuel lines, pumped out the gas from my fuel tank, drained my engine of the bad fuel, replaced the fuel pump and filter, replaced all 4 fuel injectors, and had to replace my distributor (because it had burned out...). The repairs were good enough to get me 400 miles away from Las Vegas (back to my home in CA), and it's been over a week since the incident.

However, 3 days ago, my car started shaking again and the engine light started blinking. I immediately pulled over and called a tow truck to take it to my mechanics. By the time my mechanic got to look at it yesterday morning, the car wasn't showing any signs of shaking at all. He let me take it back that day, and I drove it around a bit with no problems. But obviously, there's a problem somewhere.

At the time when it started shaking again, my gas tank had been down to 1/4. Do you think there could still be remnants of the E10 gas in my tank? I'm really at a loss of what to do.

My friend suggested that I fill my tank with premium gas for a tank or two to flush it out. Would that hurt my car? I typically fuel with 87 octane and my manual says that 85 is the minimum.

He also suggested that I try using seafoam. But I don't know what it is and it sounds intimidating...

I would greatly appreciate any advice I can get.

  • 5
    Do you mean E85 (85% Ethanol)? E10 would not have done that to your car. Commented Apr 14, 2015 at 15:17
  • Nope. It was absolutely E10. I double checked with the gas station.
    – plf94
    Commented Apr 14, 2015 at 15:23
  • 5
    Where do you live? You've been putting E10 into your car for the entirety of its life. It's very difficult to find pure gasoline and it costs an arm and a leg. I paid a 30% premium for E0 91 to get an 12% improvement in fuel economy over E10 93 when I ran an experiment to use pure gas for a few months in a row during 2014. (pure-gas.org lists gas stations that users have found selling E0 fuel. Note how tiny the list is.)
    – Eric L.
    Commented Apr 14, 2015 at 22:20
  • @Eirik - If you see, there are actually 9,215 stations listed throughout US & Canada ... That's quite a few. I believe the list is a blanket coverage for a certain area. Click on the State/Province code to get a complete listing for your area. The website is a great find, that's for sure! Commented Apr 16, 2015 at 15:20
  • 1
    Well, with ~168,000 gas stations selling gas in the US (2004) and ~11,500 in Canada, that works out to roughly 5% of North American gas stations offering some kind of E0 fuel. A large percentage of those E0 stations are at race tracks, selling 100+ octane racing fuel. fueleconomy.gov/feg/quizzes/answerQuiz16.shtml macleans.ca/economy/business/…
    – Eric L.
    Commented Apr 16, 2015 at 16:38

3 Answers 3


I would suggest that the original problem was not the use of E10 (the vast majority of all gas sold in the US is E10 fuel due to federal mandate), but rather you received a ration of bad gas which probably had water in it, or was old gas (had been sitting for a while without new gas infused in the mix). I don't think there are any remnants of the bad gas in your tank, especially after the first mechanic pulled all of the fuel out of your tank, then you ran 400 miles on at least one refuel after that.

My friend suggested that I fill my tank with premium gas for a tank or two to flush it out. Would that hurt my car?

While premium fuel won't hurt your car, it won't help it either. In fact, it will probably lower your fuel mileage while using it. Higher octane fuel doesn't burn as well as lower octane fuel. The general rule of thumb is to use the lowest octane fuel your car can handle. This will help your pocket book as well.

He also suggested that I try using seafoam. But I don't know what it is and it sounds intimidating...

Seafoam is nothing to be afraid of, as I've stated many times before. Take a look at this thread and this forum post on the subject. It may help your vehicle out and is a relatively cheap way to clean things up.


This is unrelated to the use of E10. Almost all, if not all modern vehicles can use E10. Concentrations above 10% Ethanol, E15 for example can cause problems in cars not designed for it.

What you are describing is a misfire, and it's likely cause is in the ignition side. Spark plugs, wires, etc.

Check for history codes, if your check engine light was flashing it stored codes that can help us further diagnose your problem.


Puregas.org was interesting. I looked at the 4 states I've lived in adulthood to see if I've been to any of these. It turns out that I've been to the Wawa in Fredericksburg, VA one time (since it was right off I-95) [I think maybe on the way to Richmond.]

I saw one of the stations was 1 mile from my high school. I remember driving by that Sinclair sometimes, and I never got gas there because Sinclair was always more expensive than any of the other stations around.

  • This does not answer the original poster's question.
    – SteveRacer
    Commented Sep 6, 2018 at 1:17

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