Fuel pressure bleed off

[AntMan]

On my 87 BGN running a TE-60, 50lbs. Injectors w/chip for 50lbs. Injectors my adjustable fuel pressure regulator stays around 40lbs when running with vacuum line on. When the engine is not running and I turn the key to engerize the fuel pump fuel pressure goes upto 40lbs. After the pump turns off fuel pressure drops immediately to 20 then bleeds down to 0 after 30-45 seconds. Have changed the feed and return o-rings off the fuel rail (both purchased from dealer).

Any other ideas?

 

[TexasT]

Something isn't holding the pressure. Fpr, injector(s), fuel pump in tank.

Posted from the TurboBuick.Com mobile app

 

[AntMan]

Injectors are new, put two known good FPR on same symptom and fuel pressure. Does the fuel pump hold pressure after it turns off?

 

[earlbrown]

The fuel pump has a check valve that can leak, as can the hose from the pump to the hanger. Unless you're still running that stupid pulsator, then that's another leak waiting to happen.

 

[AntMan]

Thanks earlbrown that has got to be the problem b/c I've checked and changed everything!

 

[AntMan]

Looking at the walbor 255 pump, the kit does not include a pulsator what can I use in it's place?

 

[Joel A. Russo]

Nothing. Remove the pulsator and use the short hose that comes in the kit.

 

[AntMan]

Got it thanks

 

[earlbrown]

and cut off the tip of that hose that's necked down with the rolled lip

 

[GNRick]

and cut off the tip of that hose that's necked down with the rolled lip

Well it isn't really the hose that's necked down, it's the metal line that the hose is clamped to. But we knew what you meant!

 

[sscamino]

How long should it hold pressure and how much is normal per hour?

 

[whitehot1]

My fuel system pressure takes about 30 mins. to bleed off to zero after turning the engine off.

 

[delcowizzid]

Mine returns to 0 imediatly i run a tre performance external pump with no checkvalve.my other car will hold pressure for hours if not days on end trusty oem gear lol

Sent from my C8660 using Tapatalk 2

 

[696]

My Racetronix unit does the same as the OP's. Never caused a problem.

 

[S10xGN]

It shouldn't be an issue. Mine bleeds off instantly because I modded the FPR. It takes an extra "crank" while starting, but not a problem...

 

[Boostian]

I was going to ask, is this a problem? My fuel pressure is fine at idle and under boost, but does bleed off like this (fast) when primed or turned off.

Is it an issue?


From my iPhone

 

[nonosv6]

Usually on a stock setup depending on the pump , if you're bleeding off fuel pressure within several minutes of shutting the car off you probably have a leak in the system somewhere. Whether it be an internal or external leak. As stated could be injectors regulator pump fuel line. Doesn't mean the car will run bad but maybe a sign of things to come.

Most external pumps do not have check valves in them so when you turn off the power the system loses pressure. Where as most internal pumps do have this valve.


Posted from the TurboBuick.Com mobile app

 

[GWHIZZER]

Usually on a stock setup depending on the pump , if you're bleeding off fuel pressure within several minutes of shutting the car off you probably have a leak in the system somewhere. Whether it be an internal or external leak. As stated could be injectors regulator pump fuel line. Doesn't mean the car will run bad but maybe a sign of things to come.

Most external pumps do not have check valves in them so when you turn off the power the system loses pressure. Where as most internal pumps do have this valve.


Posted from the TurboBuick.Com mobile app

The one time I had this happen I had a fuel injector stuck open. I took them out and had them cleaned, no more problems. If you pull the dipstick and you can smell gas, you can bet there's an injector problem.

 

[nonosv6]

The one time I had this happen I had a fuel injector stuck open. I took them out and had them cleaned, no more problems. If you pull the dipstick and you can smell gas, you can bet there's an injector problem.

I agree. The one time it happened in my gn years ago same thing. Bad injectors and gas smell in oil and just in the air under the hood. Replaced injectors problem gone. But it's somewhat important to diagnose this sooner than later cause you can end up has washing the cylinder walls and doing some damage.
Now with my current build I'm running a Weldon pump and was scared the first time I shut the car off and watched the fuel pressure gauge take a dive. After calling around found out that was quite normal far external pump. Joel


Posted from the TurboBuick.Com mobile app

 

[AntMan]

Replaced pump and by-passed pulsator, now have fuel pressure after pump turns off, and holds pressure for 30-60 minutes. Again a Big Thanks to all the HELP