Need help fast!!! This afternoon!!!

[95 GT]

98 GT won't maintain fuel pressure. Need advice!

My 1998 4.6 has something going on with it. I am very worried. I bought it about 5 months ago and have had no engine trouble. It is an auto with about 55k on it. 2 days ago I noticed that it took a little long start. Maybe 3 seconds of cranking. Yesterday it took about 5 seconds. Today 7 seconds. It normally fires w/in 1 second! It is cranking fine, but not firing. Once started I have not noticed any drivability issues. Has this happened to anyone? Any ideas? I am really worried about getting stuck somewhere and getting raped for a tow. All help or comments are very much appreciated. HELP!!!
Oh yeah. Full tank of gas

 

[Na5.0HO]

Sounds like your battery is going bad... could be alternator, but I'd guess battery

 

[95 GT]

Sounds like your battery is going bad... could be alternator, but I'd guess battery

Can't be. The thing cranks like a mofo.

 

[BuffaloZone]

My 1998 4.6 has something going on with it. I am very worried. I bought it about 5 months ago and have had no engine trouble. It is an auto with about 55k on it. 2 days ago I noticed that it took a little long start. Maybe 3 seconds of cranking. Yesterday it took about 5 seconds. Today 7 seconds. It normally fires w/in 1 second! It is cranking fine, but not firing. Once started I have not noticed any drivability issues. Has this happened to anyone? Any ideas? I am really worried about getting stuck somewhere and getting raped for a tow. All help or comments are very much appreciated. HELP!!!
Oh yeah. Full tank of gas

If your cranking rpm's seem [normal] fast enough, then I'd guess a fuel pressure problem. You might be losing fuel rail pressure. Mine has a fuel pressure sensor, but you might have a fuel pressure regulator and it could be leaking...or maybe a drippy injector? Have the pressure tested and make certain that the pressure doesn't bleed off too much.

 

[Na5.0HO]

My mistake.. I read it as it was cranking, but slower....I'd say fuel regulator or pump then, pump being on the more likely side.

A mechanical fuel gauge on the shrader valve should give you a good start

 

[95 GT]

Could be low fuel pressure, but then why is it running normal once it starts? I thought that the max pressure is available after the pump does it's "key to on" sequence. I would expect it to run out of power @ 5600 rpm under load, not at startup.

 

[timeless2]

My mistake.. I read it as it was cranking, but slower....I'd say fuel regulator or pump then, pump being on the more likely side.

A mechanical fuel gauge on the shrader valve should give you a good start

along with a change in the fuel filter, if it has been awhile.

 

[jstreet0204]

try turning the key to on but not start for a few seconds before starting. If the problem goes away you may have a small leak somewhere that is letting fuel pressure seep out while it sits.

 

[1fast03pony]

fuel filter

 

[Zach9865]

Check the schrader valve for fuel pressure, and if there is pressure, then I am thinking either cam sensor or crank sensor. Both are prone to failure on Ford modular motors. My Mark VIII would crank and crank and not fire until I changed the cam sensor. Check for fuel pressure first.

 

[95 GT]

Still need help

Here is what I know so far.
1. It is definitely aa fuel pressure problem. Fuel pressure is fine when pump is running but slowly bleeds off about 1/2 hour after shutdown to the point where there must be little or no fuel pressure.
2. The only way to get it to start normal is to turn the key on and off 3-5 times to run the fuel pump through it's 3 second "key on" routine which brings pressure up to where it needs to be to fire as soon as the key goes to start (normal)
3. Also, if I shut the car down and start it right back up it starts perfect.

So what I need to know is what are the likely places to look for a slow leak in the fuel system between the tank and the injectors. There is absolutely NO fuel smell outside the car at anytime. And I would know because my 1995 had the vapor canister issue and it's 100 degrees out today. Also, where is the fuel filter located? Thanks for all your help and feedback. At least I know my stang won't leave me stranded.

 

[Dark Knight GT]

Check the fuel lines. Start at the gas tank and slowly work your way to the front. Check for any fuel leaks or any pin holes in the lines anywhere. Also, I'de check the fuel filter and make sure it isn't the problem. If you've not changed it, I recommend changing it while you're under there. A clean fuel filter will allow for more flow than a dirty one. Have you recieved the check engine light yet ? Another place to check is your injectors. Make sure they are all connected as they should be. If you can, pull them out and have a look in them. One of them may be clogged with carbon and gunk build up. Its worth a check.

 

[Kilgore Trout]

These cars can be hard to start when warm. Could that be it? Do a search for "warm start problem" if it is...

 

[Kilgore Trout]

Oh, ok... I read some more of your posts in this thread and based on that additional info I now really think it is your fuel filter.

 

[mrvax]

Fuel pump or fuel filter on the way out. Change the filter first.

 

[Orions98GT]

Mine did the same thing got it at 55 k miles also. Changed the fuel filter no go. Went to the fuel pump and Bingo! starts on the first turn everytime. Try that GL

EDIT: I was cranking my almost 5-7 times to get it running before pump replacement.

 

[blackink00]

my 98 is the same way right now. been like that for about 6months now. the crappy thing about a 98 is that there is only 1 upgraded fuel pump that ive found for that year and its only like a 190lph. i think stock is 90.

 

[Orions98GT]

my 98 is the same way right now. been like that for about 6months now. the crappy thing about a 98 is that there is only 1 upgraded fuel pump that ive found for that year and its only like a 190lph. i think stock is 90.

here ya go.

GRANATELLI 255 Liter In-Tank Fuel Pump

http://performancecenter.com/produc...icle+Specific/sf5_4.6l/partnumber_GRAGM255LP/

 

[nex2nutin]

I wouldn't be surprised if after you change the filter that the pump goes bad, but also remember there is a fuel strainer in the gas tank. Sometimes they colapse causing a restriction before the fuel pump.

 

[Skidzz]

Yea sounds like a fuel delivery issue to me. Relax.....couple hundred bucks to fix at the most probably. Lol but you better get used to fixing little things like this. These cars are pretty solid, but they aren't toyotas.