All Gas from Same Pipe?
87 Octane is recommended for our old lemonzine and we've used it for 10 years 55K miles no problem.
Last week we got a full tank of gas in Roseburg, OR, supposedly 87 Octane, Mobile Station, (sign said Tesoro), and our 95 Crown Vic knocked under load so bad I actually feared for the pistons. Never heard an engine knock like that ever. Gas burner or Diesel. This was NOT pinging. Not only steep back road adverses but freeway driving too (Oregon is spelled h-i-l-l-s).
Well I backed way out of it and finally eased far enough along till we could get enough good "Union 76" 92 Octane into it to balance out the other which cured the problem.