So, I recently had to put in a new PS pump on my 07 w/ 5.4. Did all new lines, and I cannot seem to get the pressure switch port to stop leaking. I've bought a new sensor with a new fresh O ring, put in a new o-ring, replaced the line AGAIN in case it was out of spec, and no matter what I do, it still will leak. My next solution is to put a copper washer in it like a brake line, and torque it down. Has anyone else had such issues with these things?

 

Have you tried thread sealant with the o-ring?

 

Sure have, teflon tape of a couple types.

 

Take a good look at the female threaded end (down the hole) and make sure there no other o-rings in there. Double o-rings almost always leak.

 

Ok, I just checked it again, and I think the level has kept where it was for the past 4-5 days. So we might have it licked, and the first new hose was a problem.