I just installed a brand new Racetronix fuel pump. It has been in for about 3 weeks now. I also have an AutoMeter electric fuell press guage installed in the car. Right after I installed the Fuel Pump, my first fuel pressure guage crapped out on me, so Autometer sent me A brand new one. With the new one, when I turn the key to the ON position, the fuel pressure shoots instantly to 40+ psi, then right down instantly to 30 psi. Then it takes about 30 seconds and repressurized slowly back to 39-40 or normal. When turning the car on, it seems fine @ 39-40 psi.

Is this normal? Also, is it normal for the Fuel Pressure to lower to about 37 psi while decelerating in gear? Then come back up to 39-40 when stopped?

TIA

 

I wouldn't worry about it too much. Mine goes up, then drops back down to zero with the key in the on position- my afpr drops the pressure quickly to keep the load off- either that or I have a really bad leak

As long as it stays constant when the vehicle is on (at a certain load) it won't upset your car any.

 

It would be normal for fuel pressure to go down on deceleration. The engine is creating higher vacuum at that time and the regulator uses vacuum to control the pressure. When you come to a stop, vacuum lowers from when you were previously decelerating.

higher vacuum=lower pressure
lower vacuum=higher pressure

 

ok thanks for the reply's. I guess this is normal then