EScrow

Would I get a code P0171 (lean bank 1) if I top off? I've gotten this code the last 2 times after refilling the tank. I clear it with code reader and it stays off until the next time I refill.

mitsuguy

iTrader: (2)

Nope...

you either have a o2 sensor going south, mass air flow sensor on the edge, or a vacuum leak somewhere...

probably just a coincidence...

AlexusAnja

I live in Joysey, where we can't fill our own, but when I'm out of state filling my own fuel, then I just stop when the pump stops. Plus, with gas at average $2.50/gal for regular, to top to next dollar is only .4 gallons tops, that's not going to cause havok. Plus, most people will top to really the next quarter, so if it stops at $42.01, they'll either stop, or bring it up to $42.25. Only if it's say $42.58 or something, does the attendant bring it up to next dollar, so that's only .2 gallons.

Anyway, what I'm saying is, unless you're going way overboard and topping off like to next $5 dollars or something, topping off a few cents is not going to cause malfunction. I've been topping off since I was driving and I've never received any sort of CEL for the evap. canister... and it can't be just luck.

raytseng

Well, part of it is possible damage to your car. Most modern cars should be idiot-proof enough so it won't damage anything too bad. The other part is the environment. Some cars will just overflow the extra fuel out. So while you think you're really just getting another $.50 worth of fuel, really it just goes out into the air/ground.

The government cares more about the air/ground quality from the wasted fuel then they do about your numb-skullery and damage to your car; but in this case the proper technique is good for all parties.

http://www.epa.gov/donttopoff/