Is my Fuel Pressure Reg bad?

[V8killR4U]

Previously my car was running awful as in falling on its face under boost. Well I changed the plugs in my car hopeing this would solve the problem. I have GN1's and running Autolites 103's the car idled better for sure but did not solve the problem of the car falling on its face underboost. I thought this problem was rpm specific but its not. I looked at the FP guage and seen that the car would fall on its face at around 42-45 psi. Its like the Fuel Pressue will nto go over that FP range. So simply do i have bad FP reg or could there be something else i could check. Its a Bosch FPR and came with the car when i got it. Its probably about 6 years old.

 

[my1stgn]

Wel going off what you said it could be a fuel problem involving a bad Fuel Pressure Regulator, maybe a bad fuel pump, or even faulty wiring going to your fuel pump (ie loss of power or bad ground or even high resistance in your fuel pump relay) If you have access to a vacuum pump(that also applies pressure) and fuel pressure gauge you could have the car on @ idle and aply pressure to the vacuum port on the fuel pressure regulator. I believe the rule of thumb is it should increase 1psi of fuel for every psi of pressure. Hope this helps!

 

[andy999]

My car was missing under boost with autolight plugs so I switched to NGK BKR6ES-11.Cleaned the miss up I don't think autolight plugs like the high boost 22-25 LBS.Your fuel pressure seems kinda low still it should be higher under boost try hooking a hand vacume pump to and see if it holds a vacume .

 

[V8killR4U]

Wel going off what you said it could be a fuel problem involving a bad Fuel Pressure Regulator, maybe a bad fuel pump, or even faulty wiring going to your fuel pump (ie loss of power or bad ground or even high resistance in your fuel pump relay) If you have access to a vacuum pump(that also applies pressure) and fuel pressure gauge you could have the car on @ idle and aply pressure to the vacuum port on the fuel pressure regulator. I believe the rule of thumb is it should increase 1psi of fuel for every psi of pressure. Hope this helps!

Can i get a vacuum pump from autozone or something? If so if I understand you correctly I will be able to simulate an increase in fuel pressure to see if it will go over 45lbs correct?

 

[mikestertwo]

Make sure the metal line coming from the vacuum block to the regulator insn't plugged or leaking. Does the pressure change when you remove the line from the regulator with the engine running? Can you feel vacuum on the line at the regulator when your idling?

 

[V8killR4U]

Make sure the metal line coming from the vacuum block to the regulator insn't plugged or leaking. Does the pressure change when you remove the line from the regulator with the engine running? Can you feel vacuum on the line at the regulator when your idling?

Line off the pressure does rise as normal.

 

[V8killR4U]

Is there a way to test voltage to make sure im getting the proper power to the fuel pump or a way to check for a bacd ground.

 

[V8killR4U]

well just cranked down the pressure on my FPR and it went well above 45lbs of pressure. So i dont think the FPR is the problem. What should i check next? How do i check to see if my Fuel pump is working right. What else could the problem be?