Fuel Pressure

[marcus]

I have a 91 sport, when it is cold out it hard to start, i read about the fuel pressure regulator, changed it but i hooked up a gauge with the car running within in specs, but when i shut it off it does not hold any pressure. I thought it suppose to hold at least 35psi with key on engine off.

 

[KyleC]

I'm not an expert on fuel systems but from what I understand about ours is that the fuel pump keeps the pressure in the line. When it goes bad it allows the fuel to drain back into the tank. I suppose it could leak from an injector too, but someone else who knows fuel injection will have to comment on that.

 

[Syder-1]

Howdie Marcus. Kyle is right. There is a valve that is located in the fuel pump that is responsible for keeping the fuel system pressurized. If this valve goes, then your fuel pressure will drop rapidly. That is why your truck is hard to start since it takes a few cranks to build up the pressure in order for your truck to start. Unfortunately if this is the case, then your fuel pump will have to be replaced. There might also be a leak in the fuel system or an injector.

When I was checking my fuel pressure, after I shut the engine off the pressure rose to 40 psi then slowly bled off to 18 psi over a 30 minute period.

Good luck. Hope this helps.

Syder-1

------------------
doo doo happens

 

[marcus]

Well guys i think that may be the problem because it does depressurize rapidly. How hard is it too change the fuel pump. <BLOCKQUOTE><font size="1" face="Verdana, Arial ">quote:</font><HR>Originally posted by Syder-1:
Howdie Marcus. Kyle is right. There is a valve that is located in the fuel pump that is responsible for keeping the fuel system pressurized. If this valve goes, then your fuel pressure will drop rapidly. That is why your truck is hard to start since it takes a few cranks to build up the pressure in order for your truck to start. Unfortunately if this is the case, then your fuel pump will have to be replaced. There might also be a leak in the fuel system or an injector.

When I was checking my fuel pressure, after I shut the engine off the pressure rose to 40 psi then slowly bled off to 18 psi over a 30 minute period.

Good luck. Hope this helps.

Syder-1

<HR></BLOCKQUOTE>

 

[Syder-1]

Replacing the fuel pump involves removing the gas tank. Pick up a manual ($15.00) and see if you are willing to give it a try.

Syder-1

------------------
doo doo happens