willemims

Hey guys,

I have a 2000 v6 3.8L Ford Mustang. Recently, while I was driving from Texas to Kansas, the service engine soon light came on. When I filled up at the gas station, I noticed the smell of gas. I checked the gas cap, and it is fine. Once arrived in Kansas and after not using my car for a couple of days, I tried to start my car up, but it would not start, it would only rev up and then not start. After several tries, it finally just barely starts up and running. The RPM is quite low when it starts, but then runs perfectly fine. Note that once I eventually get the car started up the first time, it starts perfectly for the rest of the day. I took my car for a diagnosis at autozone and they told me it is p0455 evap system gross leak detected. After autozone, I take it to get a inspected at a local ford dealership, and they supposedly do a smoke test and there is nothing leaking, so they reset the service engine soon light. I just tried to start my car again (after leaving sit for several days) the problem keeps occurring. Hard to start, but after about 5 tries I get the car running, and throughout the same day it easily starts back up.

Can anyone help me with the problem here?

Thanks guys,
Will

petrock

An EVAP leak would not cause a no start problem. The leak was probably a loose gas cap.

The no start issue sounds like a slow fuel pressure leak to me. In the morning, turn the key to the ON position but don’t start the car. Wait for the fuel pump whistle to stop. Turn the key to the Off position and then back to ON. Wait for the fuel pump whistle to stop and then try to start the car. Does it start easier? If so, then its a fuel pressure leak which could be something as simple/cheap as a leaky fuel injector o-ring, or a leaky fuel line fitting, or something as expensive as a fuel pump. Only a leak down test with a fuel pressure gauge will tell.

willemims

petrock,

Oddly enough, after I did what you said, my car started right up - so yes it started much easier! Today is a very cold day as well, so I think that adds to the validity of what you're saying. Thank you!

Now, what steps should I take to fix the fuel pressure problem?

I replaced the fuel pump in October of 2012. So I would hope it would not be another fuel pump.

Thanks again,

Will

BabyGT

Have you ever replaced the fuel filter?

willemims

No, I haven't. I did a little research, and before I drove my car up to Kansas, it had pretty much been sitting in my driveway for 3.5 months. During the 3.5 months it was only driven one time, and only started 3 times. That would make sense that the fuel filter would be the problem, I suppose. Does that sound about right?

Thanks,

Will

petrock

Yup, then its a fuel pressure leak somewhere between the fuel injectors and the fuel pump. Rent a fuel pressure gauge from your local auto parts store. Hook it up to the Schrader valve on the fuel rail and run a leak down test. Turn the key on once, wait for the fuel pump to stop, Note the pressure on the gauge, and then turn the key off. Do that a couple times until the pressure stops rising, keeping track of the pressure each time. Once the pressure has leveled off, turn the key off and wait. If you don’t have a leak then the pressure should hold for a half hour or so. If you do have a leak, the pressure will not hold. Once you’ve verified that you have a leak, tracking down where it is in the fuel system is just a http://en.wikipedia.org/wiki/Binary_search. Get the pressure back up to normal, with the key still in the on position pinch both flexible fuel lines by the fuel pump with a rubber padded vise grips (needle nose vise grips with some vacuum hose over the needles) then turn the key off. If the pressure holds then the leak is between the vise grips and the fuel pump. If the pressure drops like before, then the leak is between the vise grips and the fuel injectors. Then just repeat the process, moving the vise grips closer to the source of the leak until you narrow down the source of the leak.

If the leak is between the vise grips & fuel pump (e.g. pressure holds when the key is off), remove one vise grip. If the pressure continues to hold, then you know the leak is on the fuel line that still has the vise grip attached. If the pressure drops, then the leak is on the fuel line that does not have the vise grip attached.


No. A clogged fuel filter would effect fuel pressure all the time, not just when the motor is cold. However, if it has never been changed it isn’t a bad idea to change it. A clogged fuel filter could, however, cause premature failure of a fuel pump due to it not filtering as well as it should.

Fordmustang04

I'm having a problem with that same code I recently hit a curb and broke the rear axle In my 04 mustang gt then 2 days later check gas cap light came on 1 day later check engine came on with code p0457 so I bought a new oem gas cap and erased the codes 1 day later came light came back with p0455 evap gross leak not sure what it is any help ?