smr2112

So Owners Link and the manual says for a 2004 TL to avoid use
of gasoline with MMT. I live in SE PA for reference.

What they say is kind of confusing about the availability or
prevalence of this gas, but curious what others know. I
don't usually read the pumps fine print to see if it has MMT but I will
now. It says MMT can cause buildup on the cylinders and
Cat. Converter.

Anybody find this on a gas pump in the NE of US or anywhere?
Was what the brand of gas? I use Hess, Mobil and Texaco
sometimes.

I always use 93 Octane at major brand stations and have never
had a problem. But.... ????

I traded to the '04 TL from a '01 Saab 9-3. At 24k miles on the Saab,
it lost a cylinder. No sign of a problem, but never felt like the
performance was that great. Just died one day.

I burnt up one value and all
needed to be replaced! Turns out the Saab had excessive carbon
build up in the cylinders and the dealer fixed it all up fine,
head was all redone new values, cleaned up the cylinders,
ran fine after that (all under warranty) but I got rid of
the car soon after. The dealer's explaination was "I simply wasn't
driving the car hard enough" - I got spooked and dumped the
car which was otherwise OK (but the TL is way better!)

So after reading the MMT thing I started to wonder if this could
have anything to do with it. I'm on the highway at least 30 miles
a day, so I didn't see how my driving had anything to do with it,
it had to be the gas (somehow). I changed the oil on the Saab
religiously every 3k and never beat it hard. Nobody could
every explain why this might be, but could it be an MMT or
other additive - my gas station useage is basically the same.
I thought it could have been a bent value, but dealer didn't think so.

So what do others know about MMT (not MTBE)? I know gas
chemistry is complex, so just want to know if others have
encountered it. Say where you live if you have seen it or
used it past or present.

eamiller

Here's an interesting SAE paper on MMT vs. Non-MMT gasoline..

http://healthandcleanair.org/mmt/ford.pdf

vtechbrain

Although MMT is less desirable all american built vehicles have to be built and warranted to use that additive. Just like ethanol, MMT and MBTE are additives that are supposed to improve air quality by increasing the oxigenation and thus improve combustion. The problem is that none of them work since they lower the energy content of the gasoline thus eliminating any theorical inprovement in provided by fuel oxigenation. To make matters worse, all except ethanol, are persistetnt polutants that sooner or later contaminate water supplies. Those additives are simply political boondogles that do not improve vehicle performance the environment or our pocket books. They amount to governmentaql subsidies to farmers in the midwest (ethanol) and to the companies that produce MMT and MBTE. Worse yet, they are specially corrosive to plastic parts in the fuel system thus increasing car costs by forcing them to use plastics that resist their destructive effects.