I have a 2001 mustang GT with 171,000 miles. Had it since it was new, taken pretty good care of it over the years, frequent oil and filter changes, spark plug changes, fluid changes, etc. Never abused, that's probably why it's lasted so long. All in all it's been a very reliable car until recently.

It started a couple months ago where the car would just stall on me. No problem, I've had that issue a couple times over the last 15 years. IAC valve needs to be replaced, so I replace it, and it seemed to get better for a day or two, but the stalling continued.

I didn't understand why it would stall on me sometimes, but not others, I let the problem continue over the last couple months due to my laziness to goto a shop, and lack of money that I cared to spend on a car with so many miles. I knew a shop would probably charge me hundreds, if not thousands. The car might be worth $1500-$2000 if I'm lucky.

The stalling seems to happen whenever I put gas in the car. It'll be running fine until I stop at the gas station and put gas in the tank. Doesn't really matter how much, 3 gallons, 5 gallons, 10 gallons -- as soon as I put some gas, the car immediately drives like ****. I have to keep on giving it gas to prevent it from stalling whenever I put the clutch in. If I'm coming up to a stop sign, I put my clutch in, put the car in neutral, and I'm using the E-brake to slow the car down while using my right foot to give it gas , if I let go of the gas pedal for more than a second, the RPM's take a nose-dive and it stalls on me.

When the car starts the stalling problem, it'll always fire back up, but what comes with the stalling is also a lot of surging and backfiring. When I try to accelerate the car will hesitate and then suddenly go. When I downshift to slow the car down, there is a lot of very loud popping noises, I assume backfiring for whatever reason.

Just yesterday I filled the tank up, and I know exactly how much my car takes given the fact that I've owned it for so many years. I'm watching the gallons go up to 14 and that's usually about where it stops, but it continues. It gets up to 14.2 gallons and I hear leaking under the car. I hang up the pump and I take a look and for whatever reason the pump didn't shut off, it just kept pumping and there's fuel leaking down under where the fuel tank is.

I don't think I have a leak in any fuel lines or the gas tank, since there's never any gas spilled in my driveway, and I still fill the car up about as frequently as I always have in the past, so it can't be a constant leak. There must be a hole somewhere in the fill tube up near the gas cap. Could this be what's causing the car's problems? A hole somewhere in my fill tube?

It's never had an issue starting, either - until just an hour ago when I tried cranking it up, and it didn't want to start. I held the key in the crank position, while giving it gas a couple times, and after about 10 seconds it FINALLY fired up - although it had a rough idle for about a minute and ran like total **** the whole way home. Weird how it drove perfectly fine earlier this morning.

Does anyone have any clue what it might be?

 

Also I frequently get the smell of fuel coming into my car

 

If you are smelling raw gas, you obviously have a leak somewhere. As for running poorly after adding fuel to the tank, my only guess would be sediment in the fuel tank, especially with your high mileage, that gets stirred up by adding fuel and starts to clog the inlet screen of your fuel pump, starving the engine of fuel. The only way to know if this is happening is to drop and inspect the tank, unfortunately. Any trouble codes?