fuel pressure problem

[50lxtacy]

I have an 89 mustang 5.0 mostly stock. I installed a walboro 255 lph pump around last march or so. About a week ago it started running rough and having hard starts. It would pop through the intake when I tried to accelerate hard and eventually would barely run. Well I hooked a fuel pressure gauge to it today and while it was actually running it only showed 20 psi. What could cause this? Any help would be greatly appreciated

 

[jrichker]

Check the voltage at the pink/black wire on the fuel pump harness disconnect, then check the ground.

 

[50lxtacy]

Ok so I put the ground in the body somewhere and check voltage on all wires at both sides of the connector right? Just key on? It doesn't have to be running right

 

[50lxtacy]

I checked voltage and at the pink and black wire I only had 6 volts