Need Help!!!!!GN FUE

[GN Andy]

Hi everyone I am a new member , I just bought my first ever Grand National a year ago this month and have been working on it non stop. The only thing is I can't find the problem on why my car back fires in WOT or pops? I have done everything I can think of like change the intank fuel pump with a walbro 255, changed the fuel filter, spark plugs gapped at 30, replaced sending unit, put a fuel pressure regulator from kirban, fuel pressure gauge , turbo tweak chip from eric and my fuel pressure wont go above or below 20 psi. Please any help will be greatly appreciated and I will post pics of my car soon...... Just WANT To Finally Drive It Right!!!!!!!

Thank you,

 

[whitehot1]

turbo tweak chip from eric and my fuel pressure wont go above or below 20 psi.

I think you found the problem with going WOT.

I believe that chip needs to be set at 43 psi fuel pressure at idle,so you need to fix that first before trying to go WOT again. When you get that done you need to add a hot wire kit for the fuel pump.

 

[Pronto]

Fuel pressure needs to be higher and rise with boost. Don't go into boost until you solve your fuel system issues. Do you have a hot wire kit?

 

[1fastcobra]

Ck the pump sock
Make sure its not sucking shut
If your not careful u can break the plastic holding the sock open when your pushing it on the pump !! Also ck to see the fuel filter is on correct

Posted from the TurboBuick.Com mobile app

 

[turbotroy]

Do NOT attempt any more wot until you get this solved or you'll get to learn to change head gaskets or worse!

 

[Chuck Leeper]

Check the hoses above the rear end hsg. Kinked?
In tank hose leaking?
Tank vent blocked off?
Try another fuel psi ga, to verify it's not fubar.
Voltage at the pump is? Pump ground good?
Start the engine, unhook and plug the vac line to the reg. Psi go up?

 

[GN Andy]

Hi everyone once again I appreciate the help and opinions of everyone . I love this forum and turbo buick community never been part of something like this. Ok so I havent got on the car ever since it started to hesitate and pop. I did change some fuel line rubber hoses that connect to the top of the sending unit they were cracked. The car does have a external fuel pump and hot wire kit but the hot wire kit is not connected. I been thinking if its the external fuel pump?

Sent from my SGH-M919 using TurboBuick Mobile mobile app

 

[Chuck Leeper]

Hi everyone once again I appreciate the help and opinions of everyone . I love this forum and turbo buick community never been part of something like this. Ok so I havent got on the car ever since it started to hesitate and pop. I did change some fuel line rubber hoses that connect to the top of the sending unit they were cracked. The car does have a external fuel pump and hot wire kit but the hot wire kit is not connected. I been thinking if its the external fuel pump?

Sent from my SGH-M919 using TurboBuick Mobile mobile app

Sounds to me as tho you are trying to push the intank pump thru a pump that's not powered up..
Ditch the external pump, and try again.

 

[GN Andy]

Hey chuck thanks that is exactly what im thinking I actually bought the car like this with the external fuel pump already installed on it. So ill do that ditch the external pump and just run straight to the intank fuel pump

Sent from my SGH-M919 using TurboBuick Mobile mobile app