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Can anyone with certainty explain the fuel selection in the syty (749) code.
Or any other gm bin.
If it fails the "test" does it just retard the timing x degrees
Thanks
Grumpy
  Two guys golfing,
one stops for a cigar, but has no light
second guy pulls out 12" Bic to light it
First guy goes where ya get that?
Second, I got a genie, ya want one wish?
Sure,  I want a million bucks
Abbracadabra, the whole sky fills with ducks..
First says I said bucks, not ducks.
second guy, well the genei is a little hard of hearing,
do you really think I asked for a 12" Bic?.