Bad FPR?

[oehm]

While checking fuel pressure on my 86 t type, I encountered some strange results. I have my fuel pressure set to 44psi line off, and 38 psi line on. When I turn the key to the on position (engine not running), the fuel pressure immediately jumps to 44psi, but then quickly falls back to zero. If I try to start the car, fuel pressure jumps back to 38 psi, and the vehicle idles fine and the pressure stays at 38 psi, When I shut the vehicle off, the fuel pressure quickly falls back to zero. I have new (less than 2k miles) MSD 50lb injectors, ATR double pumper fuel pump, and a modified stock adjustable fuel pressure regulator. The fuel pump and regulator came witht the vehicle so I have no idea how old they are. I am thinking these drops in fuel pressure are due to a bad fuel pressure regulator. I did not notice or smell any fuel leaks comming from anywhere.

Does this sound like a bad FPR to you?
If so, what FPR do you recomend. I know that Mike Licht has a billet adjustable FPR on sale for $89.95.

Thanks for the input!

 

[rob nolan]

Could be a bad FPR or a check valve in the pump. I have the same problem with mine. I also have the ATR dual pumps. I have replaced the FPR with a billet one and had the injectors flowed and clean. So i am thinking i have a bad check valve in my pump. I only have about 1000 miles on the pumps.

 

[oehm]

Turns out it was the check valve in the fuel pump.

Thanks

 

[6SENSE]

I remember this happening before and it was my [goofy] FP gauge. Must have had air in the line?? Before messing with the fpr or even thinking about pulling the tank down [again] I undid the gauge line and put it back on. It stopped doing it Weird huh?!


Ever figure out your miss/backfire problem rob?