When was the last time the car got a good tune up? Plugs, wires, PCV, filters,
4.6s are tough on wires and in the T-Birds the motor mounts are really soft. You
have a dead miss that you didn't notice if it came on gradually. That drop is
right for one cylinder not firing. If you can't remember when the plugs and
replaced, just do it. Check for contamination in the spark plug wells. (oil,
general slimy grundge...) This is an indicator of other concerns that also need
If you ask me, I think that is probably about right. The gas milage
that is. a 4.6 is not a small motor. I have a 3.8 in a Taurus wagon of
the same year 1994. What are you doing with it? Is it mostly highway?
If it were mostly highway I would be concerned a bit more. Mostly
highway I could see 22 23 miles to the gallon. Mostly city and short
trips is going to take you into the 15 mpg range. You have to figure
more into things then a tune up or the o2 sensor. A lazy transmission
which it probably has by now will add to the mpg problems. In 12 or 13
years the engine is getting lazy too. It will not give the same mpg
that was posted on the sticker even with the best care. Being in Canada
it is colder then down here in the states and that has to make for
expensive cold starts. I know in the winter my car loves to burn fuel
on a cold start. How clean is your fuel system, dirty injectors will
cause problems also. Every two weeks or so I run injector cleaner with
the gas just to keep it clean. A tune up is worth a try too. How does
the engine run in general in your opinion? I don't think anyone checks
timing of the motor anymore but it is worth a look. I still don't
understand myself why these O2 sensors don't throw a flag as they used
to in the early days. At that time it was a preset flag, but I would
think today they could show health. Yeah at .50 a liter it didn't
matter! Smile... Should never have been a 3.8 or a 4.6 in 1994 with
exception to the trucks used for industry.... I had one only for
My guess is you are off on the math AGAIN. If you had a SUPER SERIOUS
problem, the vehicle would not run well. Many stations are adding more
alcohol to the blend and that could be a factor. During the hurricane
aftermath, outlets were allowed to sell blends they would not normally
be allowed to market. You might have been getting ALL gas for awhile
and not are back to an E10 blend.
I still say it's the math though.
An E20 blend (20% ethanol) would reduce gas mileage by about 5%, going from
20 to 19 mpg. That is less than what the OP describes. However, winter
driving could make a difference, especially if the tyres are low in air, and
the driver makes short drives without the motor being warm. Low tyre air
pressure and cold motors make cars less efficient. They also add oxidizers
to fuel (MTBE and methanol being two of the chemical that are used) in
winters to help prevent pollution. These also decrease fuel mileage.
Well every time I fuel-up I get a nice printed receipt that shows
exact gallons purchased. It shows gallons to the 3rd decimal place
even. Also I reset the milage gauge at every fill-up I make.
If my math is off then perhaps I should buy either a new calculator or
get a refund for Microsoft Excel?
I don't see how I could be wrong. All you do is divide the miles
driven by the number of gallons required to fill the tank SINCE you
last reset the gauge and filled the tank.
I do however like a mystery, so if you could show me a 'new' method of
calculating MPG then by all means let me know.
I am always open to new ideas as it relates to division.
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