bimmer95
02-01-2005, 03:32 PM
In the first year and a half of our 318ti being DASCed, I always
filled up with BP 93 octane fuel and never once experienced any
pinging. Well last summer the BP station right around the corner
from us closed, leaving a Mobil station as the most convenient place
to fill up. Then an Exxon (same company) started doing an "all
grades for the price of regular" special every Tuesday, so I switched
over to running Mobil/Exxon 93 at every fill up. When I drove the
318ti (it's Lisa's daily driver) over the next few months , I thought
that I was hearing pinging, but dismissed it as a "loose exhaust
heatsheild" that I would fix later. In November I had my M3 dynoed
and was suprized to see a very jagged curve, historically it's been
very smooth.
A couple days later I put two and two together, I filled up the 318ti
with Sunoco 94. Instantly the "loose heatsheild" disappeared and the
surges in acceleration smoothed out completely. Next fill up, I ran
a tank of Shell 93, that worked just as well. Over the last two
months, I've always filled both cars with Shell 93 and haven't
noticed any problems at all.
Last night coming home from dinner, we were driving the 318ti, I
tipped the throttle and heard pinging again. I asked my wife, "Uh,
what brand of gas did you fill up with?" "Mobil" she replied. Since
we were at 1/2 tank, I drove to the nearest Shell station and dumped
in seven gallons of their 93. The pinging went away in one minute of
driving and the hesitation at WOT, that I noticed earlier in the
evening, was gone.
Hence my conclusion: Exxon/Mobil's gas sucks.
filled up with BP 93 octane fuel and never once experienced any
pinging. Well last summer the BP station right around the corner
from us closed, leaving a Mobil station as the most convenient place
to fill up. Then an Exxon (same company) started doing an "all
grades for the price of regular" special every Tuesday, so I switched
over to running Mobil/Exxon 93 at every fill up. When I drove the
318ti (it's Lisa's daily driver) over the next few months , I thought
that I was hearing pinging, but dismissed it as a "loose exhaust
heatsheild" that I would fix later. In November I had my M3 dynoed
and was suprized to see a very jagged curve, historically it's been
very smooth.
A couple days later I put two and two together, I filled up the 318ti
with Sunoco 94. Instantly the "loose heatsheild" disappeared and the
surges in acceleration smoothed out completely. Next fill up, I ran
a tank of Shell 93, that worked just as well. Over the last two
months, I've always filled both cars with Shell 93 and haven't
noticed any problems at all.
Last night coming home from dinner, we were driving the 318ti, I
tipped the throttle and heard pinging again. I asked my wife, "Uh,
what brand of gas did you fill up with?" "Mobil" she replied. Since
we were at 1/2 tank, I drove to the nearest Shell station and dumped
in seven gallons of their 93. The pinging went away in one minute of
driving and the hesitation at WOT, that I noticed earlier in the
evening, was gone.
Hence my conclusion: Exxon/Mobil's gas sucks.