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RE: MPG Survey & CA new gas formula

This is the info I was refering to a couple of months ago Jim.  You may recall my assertion that the new formulation of gas used in California (which is different and more extreme than those used in other states) caused significantly lower mileage.  I finally tracked down the article and references.

This is also to help explain to the rest of you why we Californians seem to be whining about our gas.  It's because we really do have something to complain about.

Kevin Toney
'70 Sqbk/Variant
'71 Sqbk/Variant
'85 Golf
'85 Vanagon (Dead) 
"Anyone who cannot cope with mathematics is not fully human.  At best he is a tolerable subhuman who has learned to wear shoes, bathe, and not make messes in the house."  L.L.

Ed Note: This article, originally published in the fall edition of the California Automotive Teachers (CAT) Association newsletter has been reprinted with the permission of the author Rick Escalambre. A member of the CAT Board of Trustees, Mr. Escalambre is on faculty of  San Bruno-based Skyline College's Automotive Technology department. For more information about the CAT, write to the group  3574 Hatfield Circle , Oceanside, CA 92056.

 In the San Francisco Bay Area, reformulated gasoline (RFG) has created a quite a controversy Since last  May, it has become an issue that has stirred up considerable media attention. After receiving numerous  complaints from local viewers, KGO-TV an affiliate of ABC, began an investigation into reformulated gasoline.  The investigation included Skyline College's Automotive Technology students, the California Resources Board  (CARB), K N Filters, an independent Smog Check station, an expert on rubber hoses.  Background: What Is RFG?

The reformulation gasoline (RFG) program is one of the latest in a series of measures taken to provide leaner burning automotive fuels. RFG is often confused with oxygenated gasoline. While both contain oxygenates, such as ethanol and MTBE, they are not exactly the same. Oxygenated fuels are simply  conventional gasolines with an oxygenate added.  Oxygenated fuels are sold during the winter months to reduce CO emissions.   RFG gasolines contain oxygenates but undergo other compositional and property  alterations to reduce ozone forming emissions. RFG is a year round program.   The primary differences between RFG and conventional gasoline are as follows:  
 1. Benzene is limited to 1% in RFG.
 2. Volatility is reduced in summer grades of RFG.
 3. Every gallon of RFG must contain oxygenates.   An oxygenated gasoline is oxygenated by the addition     of an alcohol or ether. The most commonly used alcohol is ethanol and the most commonly used ether is MTBE.
The primary oxygenate used in RFG is MTBE (Methyl Tertiary Butyl Ether). MTBE is used as an octane enhancer, It is not as sensitive to water as are alcohols and does not increase the volatility of most gasolines.  

 At the same time, it is the additive that is creating much of the controversy. Reports indicate that it is the additive responsible for removing the compounds in fuel hoses responsible for preventing leaks.

Independent Tests: MPG Test

 The process was initiated at my college. KGO-TV asked if we would conduct a dynamometer test using a reformulated and non-reformulated fuel. We gladly g accepted the challenge. They provided us with two gallons of non-reformulated fuel purchased from Nevada and two gallons of  California's reformulated. 

 Using my class of advanced engine performance students and our Clayton Dynamometer, we conducted a series of steady state fuel economy tests. The vehicle used was a well maintained 1990 Oldsmobile - front wheel drive, 3800 V6 engine, and four-speed automatic transmission.  

 All fluid levels were checked and tire pressure was set to 32 psi The vehicle was run until it reached operating temperature.  The vehicle was prepared as if the fuel injectors were to be cleaned. We used an OTC injection cleaner canister, disconnected the fuel pump and pressure regulator, and set fuel pressure to 32 psi. This was lower than specifications, but it assured us that no fuel would be returned to the fuel tank.

 All tests were conducted by the same driver. Another student monitored the data stream using a Monitor 4000. This allowed the driver to achieve the same throttle position and mass air flow during each test. 

 The dynamometer load was set to ten horsepower at forty-five miles per hour. This was equivalent to a light load cruise.

 The results were very obvious, The non-reformulated produced a 26.49 mpg and the reformulated fuel produced 24.91 mpg, or 1.58 mpg less.  This equated to a 6% difference, almost double CARB's prediction of a 1 to 396 decrease in overall mpg. 

 What better way to conduct the test? We weren't concerned with radical changes in acceleration and deceleration, air conditioning and power steering loads, or extended idle conditions. While this is not as scientific as Federal Test Procedures (ETP), it was a good comparison of two different fuels tested under identical conditions.

Horsepower Test

A few days later, KGO visited K & N Filters in Southern California. K 8 N conducted an inertia  dynamometer horsepower test using both types of gasolines. Their tests produced a 5% decrease in horsepower using reformulated fuel.

 Further investigation by KGO showed that consumers were flocking to the parts stores to buy fuel tank additives in an attempt to regain fuel economy and horsepower.

BAR '90 Smog Check

 At this point in time the test results show 6% decrease in mpg and a 5% decrease in horsepower to the drive wheels.  

 Overlooking the decrease in MPG and horsepower, KGO-TV attempted to identify the main goal of reformulated fuel, which is to reduce air pollution.

 A BAR '90 two-speed idle Smog Check was conducted at our facility using the same 1990 Oldsmobile used in the MPG test. Both types of fuel were tested and the results were almost identical. Idle and 2500 rpm produced 6 ppm HC and O% CO.  Obviously, the converter was doing its job.

 During the following week KGO-TV visited an independent repair shop licensed to perform Smog  Checks. They performed the smog test using a 1974 BMW without a catalytic converter. The differences were appreciable. The non-reformulated gasoline produced 101 ppm HC and 3.94% CO at idle and 54 ppm HC and 2.52% CO at 2500 rpm. The reformulated gasoline produced 82 ppm HC and 3.54% CO at idle and 64 ppm HC and 4.19% CO at 2500 rpm. 

 Obviously, the reformulated gasoline produced lower HC readings, but CO reading at 2500 rpm was  significantly higher. Keeping in mind that the new fuels aimed at reducing emissions. it has also failed  this test.

 CARB officials claim the new gasoline was tested in over 800 vehicles driven five million miles using  500,000 gallons of gasoline. CARB reports the new fuel will reduce toxic air pollution by 15%. In  addition, it will reduce cancer causing  Benzene by 50%. CARB sources claim it is the world's cleanest burning gas.
John Dunlap, Chairman of the Air Resources Board, also stated that the new fuel is the equivalent of removing 3.5 million vehicle from our roads. It is also 25% of CARB's plan for ozone reduction and will remove 300 tons of air pollution from our atmosphere.

 Mr. Dunlap reports that complaints of decreased mileage and performance are related to poor vehicle  maintenance and driving habits and not the reformulated gasoline. He claims that some of the complaints might have been caused by the warm weather and the use of air conditioner which can reduce MPG by as much as 20%.  

Impact on Rubber Lines

 Another investigation by KGO-TV dealt with the impact reformulated gasoline have on rubber fuel lines.  Mr. Dunlap states the new fuels will not damage an engine or create fuel leaks that might cause a fire.

 If this is the case, why has Chevron posted signs on their pumps warning that the new gas may cause fuel leaks? KGO-TV also reported that Chevron has warned their retired employees of the new fuel leak  problems.

 Another report indicates that car fires are up 109b this year compared to the same time year. Nissan currently has a recall campaign for many of  their mid 1980 fuel injected vehicles. This because the MTBE in the reformulated gasoline attacks the elastomers used in the rubber hoses causing them to leak.

 The Rubber hoses in question are made of Nitrile which is used in vehicles prior to 1991. In California, this equates to 15,000,000 vehicles that are equipped with this type of fuel lines.

 Independent tests have shown that MTBE attacks Nitrile parts in the fuel pump, fuel filter, fuel tank, fuel  injectors, fuel pressure regulator, and fuel rails. While CARB denies these reports, their own field  investigators report that many of the problems they are seeing are directly related to the fuel leaks.

 A spokesman for the American Chemical Society and Rubber Manufacturers Association reported that  MTBE increases the chances of fuel leaks in vehicles built prior to 1990. SAE, Dupont, 3M, and Zeon  Chemicals have all confirmed that MTBE does breakdown Nitrile rubber parts. How much Nitrile is in a complete fuel system? It is difficult to tell because manufacturers will not release this information. 

 Reports show that aftermarket rubber parts may still contain Nitrile.  


 The tests conducted at our college, K 8 N Filters, and the independent repair shop were performed, at the request of KGO-TV in an attempt to validate consumer complaints. The complaints registered by  consumers were verified by the 6% decrease in mpg, the 59b decrease in horsepower, and the increase of 1.5% more CO, during a 2500 rpm smog test.

 It is evident the CARB has become very defensive and somewhat hostile about the new gasoline. This is  probably because they want to avoid another "Diesel Fiasco" which occurred in 1993-94. This resulted in  

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