Contour Enthusiasts Group Archives Forums General Troubleshooting Chevron gas and Check engine light.

The reason that Arco gas gets a bum rap is due to the 10% ethonol additive. In colder climates the ethonol causes a loss of power. In California it is probably not cold enough to cause the problems.

The Ethonol is put in to lower emissions in cold weather but it does that mostly by lowering horse power which is harder to produce in cold wheather.