P71 Crown Victoria/Police Interceptor
4.6 ltr SOHC.. I think.
The only thing I have tried is every different nozzle position I can think of..none work. It acts like the tank is full, to the point that fuel will gush out if I attempt to fill it too quickly and I dont have the nozzle seated well. I can only add fuel at a trickle or the pump clicks off. Don't know if it's related in any way, but my mileage is horrible as well :) less than 15MPG.
The reason your tank won't fill is that down where the filler neck meets the fuel tank there is a antisiphon flapper valve. It prevents hoses from being placed down the filler neck into the tank to siphon gas out. The flapper valve is closed and not letting gas to flow quickly into your tank. That is why it shuts the pump of and spashes back when filling it fast.
The picture shows a Lincoln, but it is the same as the Crown Vic.
The filler neck can be replaced without dropping the fuel tank. As for the gas mileage, you cna get your ECU reporogrammed which will reset all the tables (programs) in your ECU and the gas mileage should improve. The ECU uses Adaptive Strategies, basically it learns how you drive and adapts to your habits, or the previous owner. It basically learns as you drive. You can also disconect the battery for 10 minutes and se if the gas mileage improves. But the best way is to have your ECU reprogrammed with the latest calibrations. I hate to say this, but the best place to have the reprogram done is at a dealership.
You are welcome. I can give you directions on replacing the filler neck it you want to try to.
CAUTION: Do not damage retainer ring during removal or the cap may not seal.
CAUTION: The dogpoint screw has a blunt end and must be used in this application.
CAUTION: Exercise care not to damage grommet or check valve at end of pipe (9072).
NOTE: If unable to obtain sufficient clearance for removal, the tank straps may have to be loosened.
NOTE: Lubricate the fuel tank filler pipe end with petroleum meeting Ford specification ESW-M1C115-A or ESB-M1C99-A.
NOTE: Screw has a blunt end and must be used in this application.
NOTE: Attach strap for cap at 4:00 o'clock position.
Here are the directions. Look it over and look at the Crown Vic. See if you want to do it before removing any parts. As for the special grease, you can use WD40 if a very light coat of regular grease.