So many friends of mine fill up their bikes and cars with the least expensive gas available. Often they use the Gas Buddy app to locate the gas station selling at the lowest price per liter. When I talk about gas quality they shrug it off as a “gimmick” by the big oil companies and that in Canada and the United States we have standards that all gas must meet.

The EPA did establish a minimum detergent requirement for all gas suppliers in 1995. The detergent in gas is very important to maintain emission standards by preventing build up of engine deposits. Engine deposits not only have a detrimental affect on emissions but also on performance such as acceleration and gas economy.

Base Fuel:

The base fuel shall conform to ASTM D 4814 and shall contain commercial fuel grade ethanol conforming to ASTM D 4806. All gasoline blend stocks used to formulate the base fuel shall be representative of normal U.S. refinery operations and shall be derived from conversion units downstream of distillation. Butanes and pentanes are allowed for vapor pressure adjustment. The use of chemical streams is prohibited. The base fuel shall have the following specific properties after the addition of ethanol:

  1. Contain enough denatured ethanol such that the actual ethanol content is no less than 8.0 and no more than 10.0 volume percent.
  2. Contain no less than 8 volume percent olefins. At least 75% of the olefins shall be derived from FCC gasoline as defined by CARB (advisory letter, April 19, 2001).
  3. Contain no less than 28 volume percent aromatics as measured by ASTM D 1319 or D 5580.
  4. Contain no less than 24 mg/kg sulfur as measured by ASTM D 2622 or D 5453. At least 60% of the sulfur shall be derived from FCC blend stock.
  5. Produce a 90% evaporation distillation temperature no less than 290F. as measured by ASTM D 86.
  6. Produce IVD no less than 500 mg averaged over all intake valves.


The base fuel from shall contain enough deposit control additive such the IVD is no more than 50 mg averaged over all intake valves. Results for individual valves and an average shall be reported. The unwashed gum level of the fuel containing deposit control additive shall be determined according to ASTM D 381 and reported.

So why should we look for top tier gas resellers?

The intention of the TOP TIER Detergent Gasoline standards is to create a winning situation for gasoline retailers, auto manufacturers and drivers.   Currently, many gasoline retailers provide fuels with lower-quality additive packages that can build up deposits on fuel injectors and on intake valves.  Others can build up deposits in combustion chambers and may lead to intake valve sticking.  These lower levels of additives can have negative impacts on engine performance and vehicle responsiveness.

This is especially important for smaller high revving engines such as motorcycles.

Below is a link to a video explaining this.


Who are top Tier Gas Suppliers Committed to Quality Gas?


  • Chevron Canada
  • CO-OP
  • Esso
  • Petro-Canada
  • Shell Canada
  • Tempo

United States:

  • Aloha Petroleum
  • ARCO
  • BP
  • Chevron
  • Conoco
  • Costco Wholesale
  • CountryMark
  • Entec Stations
  • Express Convenience Centers
  • Exxon
  • Hawaii Fueling Network (HFN)
  • Holiday Stationstores
  • Kwik Trip / Kwik Star
  • MFA Oil Co.
  • Mobil
  • Ohana Fuels
  • Phillips 66
  • Quik Trip
  • Road Ranger
  • Scheirl Oil
  • Shell
  • SuperAmerica
  • Texaco
  • Tri-Par Oil Co.