This is what bad fuel looks like when drained from the filter.
Clogged fuel filters are a primary cause of pinging in fuel injected vehicle.

  By my records I picked this load up at a Shell Station
7001 E RENO, MIDWEST CITY, OK on  7 Dec 2004 from the 91 Octane pump.
It was mixed with fuel system cleaner and Sinclair 93, but only to address some light pinging
under load.  The ping as it turns out was caused by a lean condition due to fuel pressure drop.

25/Dec/2004: (or there abouts) I wrote Shell through their website and let them know about the fuel.
4/Jan/2005: Shell contacted me about my concern and request information on the repair costs. (A whole $12.64 for the filter)

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