'93LXvert

Hey everybody (I'm new here) I have a really quick but kind of worrying problem. I think my Fox has a bit of a gas leak but I am really not sure. I have never dealt with Foxes before this one, so I'm a little new as to where everything is and what the problem items are on this car. The leak seems to be coming from the middle of the rear of the car (if that makes sense). I can't quite fit under there and I haven't had time to jack it up, but I was wondering if there were any hoses, seals, or similar on that tank in that generalized area. Whenever I start the car or I am going for a while I will occasionally smell gas. I was thinking it was an exhaust leak until I found those two dark spots under that part of the car. Could it be possible that the seal up on the filler neck is going and the gas is trickling down? It seems unlikely, but I am not ruling anything out. I lost my last car to a gas fire and I sure as heck am not losing another. (Losing a fully restored IHC Scout that received three years of no-expense spared work was rather painful-- not to mention that it was my first car.) The only other things that I have noticed would be relatively crappy fuel mileage (13-15 mainly city mpg on a bone stock 'vert with the AOD) and I have noticed that the fuel gauge likes to drop a bit whenever I am cruising down the road or getting going at a light, but it bounces back up afterwards. But at the same time I parked it at three this afternoon and checked it an hour ago and the gauge read a little differently than when I parked it. I may just be paranoid and those may just be oil or grease spots from another time, but like I said I am not leaving anything to chance. So that's why I've come to you guys as you guys have been working on these cars a LOT longer than I have.

mattdel

Filler neck seal is the best bet given your description. Tank will have to come down to get the neck out. Good time to replace the sending unit and fix your gauge. Check the tank for the fuel pump baffle as well, make sure it's in place and not floating around in the gas.

'93LXvert

Well I feel like a total dipstick now. Turns out that my grandmother had parked her excursion where I park my mustang yesterday. The dark spot on the ground was not gas, but instead motor oil from her powerstroke. I think I'll replace the filler seal regardless of this.I don't want to leave anything to chance, ya know? I made sure that there is not a leak by thoroughly feeling the tank for wet spots and placing white paper under the car. That way if anything leaked, I would definitely see it. However there still is the issue of the fuel gauge. I'm tired of it acting funny on me. When I fill up it reads pretty well above full and when I am on the gas the needle droops a decent amount (depending on how hard I am on the pedal and for how long). How would you recommend fixing that? I think my iffy MPG issue will be fixed with the brand new 302 I'm dropping in here soon, so I'm not going to worry about that for now.

mattdel

Grandmother + Excursion = hilarious. Post a vid of that action.

As far as the gauge, the sending unit is the blame there. It's in the tank.

Project 5.GO!

Yeah, I had the fuel needle go nuts on me too. 100%, it's the sending unit in the tank. I dealt with the swinging gas needle for waaaay too long, considering how easy the job was. Only regret is that I didn't do the fuel pump while I was in there. I did look over the inside of the tank, and after 300k miles, I was expecting the gunk that people claim to be lurking in the bottom of the tank, but it was spotless.