[email protected] (Dave Williams)
fordnatics  16 Sep 1995
- -> Also, most PREMIUM fuels should not be using MTBE or ethanol to
  -> increase the octane.  If you are using good brand (Amoco, Shell,
  -> etc...) gas, this will not be a problem, at least not in my neck of
  -> the woods (Tampa FL).  All methanol additive gas has a clear label.
- If only it was so all over.  Around here, anything over 89 usually has some 
  amount of alcohol or MTBE in it.  It used to be easy to tell with when the 
  rotary engine was in the RX, because you had to drive around with the choke 
  on.  The early carbureted models were 'way lean to start with because the 
  rotary is inherently dirty; leaning the mixture out more by adulterating the 
  fuel caused bad trouble.  Some cheap brands of regular apparently have a 
  *lot* of MTBE in them - besides hard starting, stumbling, surging at cruise, 
  and all that, the exhaust smells horrible. 

[email protected] (Dave Williams)
fordnatics  11 Jan 1997
- -> > 3-4%... BUT cars need 3-4% (again guestimate figure) MORE gas to do
  -> the > same thing!  So where is the savings?!?!?
- > There isn't any savings on your car.  The whole point was to "trick"
  > the carbureted cars into running leaner...
- Unfortunately most second and third gen smog carb setups are on the edge of 
  lean misfire to start with.  Oxygenated fuel not only makes them run like 
  crap, the subsequent misfires drive HC through the roof. 
- The oil companies like oxygenated fuels because the oxygenate component of 
  the fuel is not taxed as heavily as the petroleum component.  They, of 
  course, not only pocket the difference, they also jack up the price at the 
  pump. 
- Some areas add so much MTBE or ETBE that some closed loop EFI ECUs don't 
  have the range to correct for running on that sort of camel piss. 
- Of course, the OFFICIAL word is that oxygenates are a universal win. There 
  are no problems or drawbacks, you dirty little troublemaker... 

[email protected] (Dave Williams)
diy_efi  09 Jan 1997
- -> Excuse my ignorance:  Is this (MTBE) what oxygenates the fuel
  -> in Calif?  I've noticed my car pinging *more* since this gas started
  -> being used year round.  Yet I believe someone said this adds
  -> octane.  Did I remember that wrong?
- Crazed psychotics (such as myself) have observed even closed-loop EFI 
  engines sometimes have trouble with fuel heavily contaminated with MTBE, 
  which can lean the engine out past the learn limit of the ECU.  Of course 
  this is pure BS, as many OFFICIAL STUDIES have PROVED no such thing can 
  happen.  MTBE is GOOD for you.  Just sit right here in this chair, comrade, 
  while we hook up these nice electrodes... 
- MTBE is bad news in fuel.  It is put in fuel for political reasons, not
  chemistry.

[email protected] (Dave Williams)
fordnatics  03 Nov 1997
- -> What is this stuff made of, octane ratings and what is the general no
  -> good it's gonna due for probably a higher price.
- The major part of the "reformulation" is to lower the vapor pressure, that 
  is, how easily the stuff evaporates.  This can cause big problems in 
  carbureted cars.  Usually reformate base stock is blended with oxygenates, 
  usually MTBE or ETBE, which smell bad and have the charming habit of 
  dissolving some rubber components, like fuel lines.  And the oxygenates also 
  play hob with carbureted cars, and even manage to freak out quite a few EFI 
  cars at idle, where most of them are running on a data map instead of closed 
  loop. 
- Pump price will go up, gas mileage will go down, emissions in general will 
  go 'way up due to the lean misfire problem, and you can drive while basking 
  in the warm assurance you're going your part to ease the conscience of the 
  EPA while filling the coffers of Standard Oil and your local gas stations.  
  Amen. 

[email protected] (Dave Williams)
capri  13 Oct 1998
- -> MTBE is a great gasoline component for performance.  It is about 110
  -> octane and boils just where you need that octane, not in the heavy,
- Lots of vehicles won't even *run* on gasoline with very much MTBE, my Yamaha 
  and the 12A rotary I used to have in my RX7 being good examples. Even 
  closed-loop EFI vehicles often have problems with MTBE in gasoline; GM has 
  issued half a dozen service chips on various carlines to reduce customer 
  complaints.  And when you do tweak the vehicle to run on it, your gas 
  mileage goes to hell in a handbasket; my Capri will drop from 22 to about 
  16. 
- In the case of the Yamaha, the MTBE ate the rubber fuel lines, stopped up 
  the pressure regulator, fuel pump, and carbs, and caused over $500 in 
  repairs - just for parts.  Everything in the fuel system was clogged with 
  the black goo it turned the rubber into. 
- You can keep your MTBE.  And as for performance... thanks, I'll take 
  gasoline. 

[email protected] (Dave Williams)
capri  14 Oct 1998
- -> I am puzzled.  Something doesn't make sense.  I am sure the fuel is
  -> not the source of your problem, even though it sure sounds like the
  -> most likely cause of the symptoms you described.  If you ever figure
- Oxygenated fuels are supposed to reduce emissions of '70s and early '80s 
  carbureted vehicles running without closed loop computer control.  The 
  official story is these vehicles run rich and emit lots of HC.  This is in 
  fact untrue; these carbureted vehicles were calibrated very lean, right up 
  to the point where driveability became an issue.  Oxygenated fuels lean this 
  out further, to where the engine is running in the lean misfire zone.  The 
  HCs then go through the roof, but the emperor has no clothes, at least in 
  this topic.  The percentage of cars oxygenated fuel is *theoretically* 
  benefiting is small and dropping continuously as those cars are retired from 
  service. 
- -> roughly 25% you observed.  Gasahol fuels (containing ethanol) should
  -> give similarly lower fuel economies compared to "real" fuel, so I am
- Gasohol is no longer common in my area, but when it was, mileage dropped 
  very slightly.  The major noticeable difference was harder starting and 
  longer warmup in cold weather, but overall not too bad, certainly not on the 
  order or MTBE or ETBE. 
- Oxygenated fuels have nothing to do with automobiles, fuels, emissions, or 
  chemistry.  Oxygenated fuels are about POLITICS.  For example, Archer-
  Midland-Daniels makes alcohol and has a powerful lobby group in DC, 
  interested in passing laws for you to purchase their product.  I'm sure 
  there's a similar financial interest in the tertiary butyl ether products.