04 Ram 1500 5.7L (155k) My fuel pump was going out. Replaced it going the remove bed route. Thanks for the directions on this. Anyway, following procedures to replace the pump, I removed the protective cap on the fuel rail test port and used a small aluminum rod to press in the shraeder valve to relieve the pressure on the system. It squirted a little, then I replaced the cap, put the air filter assembly back on. I finished the fuel pump replacement. Started the truck, success! Left to go get fuel and run an errand. Started to smell fuel. Opened the hood and saw a minor leak. Limped home. Pulled air filter assembly again, pulled the protective cap, thinking that was the only thing i touched in the engine. Tightened the schraeder valve, it was not very loose, just an 1/8 of turn to tighten. Started it up. Ran it for a while. No leak at all. Ok. I then pump the protective cap on, tightening snugly, LEAK! Backed it off no leak! That can't be normal. New fuel pump having higher pressure pushing the needle valve a little farther?

 

why did you replace the cap on the test port?? maybe the new cap is pressing on the valve core when fully tightend?

connor

 

Sounds like cap washer/Seal has gotten Knotted up inside cap and was depressing valve

 

Replaced as in put back on, I would imagine.

Check inside the cap to verify that the seal is still in there. If it fell out, the cap will screw down too far and can depress the valve.