I'm still using Chevron 94 and haven't had any problems at all.

 

if you read the s2000 manual, it says that some canadian gas companies use an octane booster additive that may affect how the s2000 runs

 

ive been sticking with 94 octane. and recently the car hasnt been having a problem starting. So im guessing my ECU has adapted to the changes.

A number of ppl coming in for service at my work place had the same problem as well. The service advisors are telling them to try 91 octane and apparently it has been working.

 

I emailed Chevron again about MMt additives and this is what I recieved.I started to use Chevron 94 because it doesn't contain ethanol. If you look up info on ethanol blended fuels you will find out that it will lessen your fuel economy but they are better for emmisions. Email below!


I would like to find out if any of your gasoline’s use MMT additives especially concerned about your Chevron Supreme plus which I use.

Thank You for your time
Mark


Thank you for your inquiry concerning the manganese additive content of Chevron and Texaco gasoline. All of Chevron's and Texaco's gasoline is Top Tier Detergent Gasoline, and none of it contains any manganese additive. methylcyclopentadienyl manganese tricarboynyl (MMT).



Again, Chevron does not use MMT in any of the gasoline marketed (Chevron or Texaco Brand) anywhere in the entire United States or Canada.



MMT is a gasoline additive. Its chemical name is methylcyclopentadienyl manganese tricarbonyl. Much like the element lead that was found in gasoline in the past (and now outlawed), MMT can increase the octane of the gasoline.



Its use is opposed by environmental groups and the automobile manufacturers. The latter contend it will foul spark plugs, catalytic converters, oxygen sensors, and combustion chamber walls. On the other hand, the manufacturer of MMT has developed a large body of data to supports its claim that MMT in gasoline does not reduce performance or increase emissions.