Fuel pressure regulator?

[Exrange]

Would the fuel pressure regulator be the cause of a hard starting problem? I have a 92 sport and recently i've had some problem starting it after it sits for a while. The cold doesn't make a difference because it was doing it when it was warm over the weekend. It runs fine after its already running. Any help would be great. Thanks in advance, Matt

 

[Ryan]

Matt

I belive im having the same problem with my 94XLT...This just started happening a week or so ago...used to when I turnd the key It fired right up......now after it sits for a while.....the damn thing cranks for 2-5 seconds before it starts .. sometimes it wont catch and it will kill on mye

anybody have any ideas??

Ryan

 

[D F Willy]

I don't know what your problem is, but if it's a bad fuel injector pressure regulator, your check engine light would come on, along with horrible acceleration, and gas mileage.

 

[Exrange]

Thanks, I'll check it out.

 

[Pete]

As far as I know the EEC is not connected to the fuel pressure regulator so if it is failing it will not trigger an EEC fault code or the 'check engine' light. I think the only way to properly diagnose the regulator (outside of an outright failure) is by using a fuel pressure testing rig. You can get one at Pep Boys or Kragen/Chief for about $45. Do a search of this site to find the other posts on the regulator and that might give you a clue. Mine failed all at once, as follows.

The regulator on my Bronco II failed completely and I got no EEC code or check engine light. What it did do was hydraulic-lock the engine by filling the entire engine full of gasoline. The diaphragm got a small hole in it, thus causing engine vacuum to suck gas directly into the upper intake manifold until the whole thing was filled with gas.

I went out to start the truck one day, it ran for about 10 seconds and then a large THUMP and the motor suddenly died. Then the motor wouldn't even turn over. I thought it had thrown a rod or busted the crank, or something. So before I panicked, I pulled all the plugs, cranked the motor and gas shot EVERYWHERE. So I got to thinking - the only way gas can get into there is through the vacuum system, and the only connection between the vacuum system and the manifold is the fuel pressure regulator. Replaced it and it started right up. Changed the oil twice since it had gotten contaminated with gas. The whole exhaust system had also filled with gas so when I drove it the first few miles I looked like a mosquito fogger. I drained out about two gallons of gas-contaminated oil - looked just like the stuff you put in your dirt bike.

 

[slow-demon]

The problem could be in your fuel pump. The fuel pump has a check valve that keeps fuel in the lines and engine fuel rails from draining back into the fuel tank when the engine is off. What could be happening is the fuel is draining back into the tank when you let it sit overnight. Try this next time you start it up in the morning or after letting it sit for a while. Try cycing the ignition to the "on" position for about 3 seconds and back to "off". Do this for about 4 times without starting the engine. After the fourth time try starting the engine. If it starts like normal then the problem is your fuel pump and you will have to have it replaced. What you are doing when you cycle the ignition is letting the fuel pump run and prime the fuel lines. When you put the ignition to the "on" position with the engine off the fuel pump runs for 3 seconds then stops and only runs again if the engine computers senses the engine cranking. So by cycling the ignition your are priming the fuel lines. Hope this helps.

 

[TPLYNCH]

Your problem might be with your ignition switch. Engine progressively has a hard time starting then wouldn't start even though battery checked out fine. Just had this problem w/my escort. Not sure if Explorer ignition setup is similar, but thought I'd pass it along......

 

[Exrange]

Slow-Demon, thanks for your help, I tryed what you said and it started right up. To make sure i did it a few more times duringthe day and it worked again. It usually doesn't take all night to do that, only an hour or two. Again,thanks a lot. Matt

 

[tonyboy123]

The problem could be in your fuel pump. The fuel pump has a check valve that keeps fuel in the lines and engine fuel rails from draining back into the fuel tank when the engine is off. What could be happening is the fuel is draining back into the tank when you let it sit overnight. Try this next time you start it up in the morning or after letting it sit for a while. Try cycing the ignition to the "on" position for about 3 seconds and back to "off". Do this for about 4 times without starting the engine. After the fourth time try starting the engine. If it starts like normal then the problem is your fuel pump and you will have to have it replaced. What you are doing when you cycle the ignition is letting the fuel pump run and prime the fuel lines. When you put the ignition to the "on" position with the engine off the fuel pump runs for 3 seconds then stops and only runs again if the engine computers senses the engine cranking. So by cycling the ignition your are priming the fuel lines. Hope this helps.

 

[tonyboy123]

I have the same problem with my 02 mountaineer. It seems that the fuel check valve in the pump has gone bad. Does anyone one know if I can add a separate check valve to the fuel line instead of dropping the tank and replacing the fuel pump.