I filled up my girlfriend`s Probe up at a Kroger the other night and a large sticker on the pumps said "contains ethynol". Is this something we need to watch out for when fueling up our Z`s? I work at a GM dealership and we sell Flexfuel(ethynol/gasoline) Tahoes. Is this gasoline containing ethynol something that should be avoided when fueling up our Z`s,or is all fuel like this "normally" being used and is harmless? Just curious because I`ve never noticed the "contains ethynol" sticker before. Thanks!