Rob,
How did you clean your tank?
I had lean-out problems several years ago. Under heavy load at 100 km/hr, the motor would start to surge and lose power. The check engine light would come on. When I slowed down, the light turned off, but it stored an error code indicating an O2 sensor/Lean issue. The problem got more and more noticeable.
Rather than just changing the in-tank fuel filter sock and main fuel filter, I took the vehicle to a radiator shop and had them coat the fuel tank with a product called 'Red-Kote', which seems to have stood up for several years.
Damon Industries - Red-Kote
There seem to be several different vendors who sell similar products, but my shop uses this so I went with their recommendation.
I thought that the inside of my fuel tank would be disgustingly rusty, but in fact, it looked almost perfect before coating.
Fuel tanks used to be steel and were coated with a coating of 'Terne, an alloy of lead usually with 2–25% tin and small amounts of zinc, nickel, and magnesium. . The amount of lead continually decreased due to environmental concerns. I believe that in the 1980's, the amount of zinc had increased dramatically.
Terne is supposed to be quite resilient, but that pesky Ethanol is hygroscopic, and draws moisture into the gasoline. This is especially an issue with a vehicle that is parked a lot, and not driven much.
There are several coating that are used to coat the inside of fuel tanks to remove. Terne should be water resisitant, but if the pH is low or high, it will tend to strip.
Gosh knows what would give the fuel a green tinge, but I suspect it is some of the Terne stripping off.
Dale
