Hi, I have been going nuts with this van and was wondering if anyone has any ideas on the problem. Last summer it would not start, random problem after it had been running, let it sit for a while 30 minutes or so, then start right up. Finally in the fall it was blowing the fuse for the fuel pump, so I changed the fuel pump in tank, used motorcraft brand new unit. Ran fine after that. A few months ago it started to do a hard starting routine, first or second cranking, nothing then it would fire right up and run fine. I used a fuel line pressure tester last week on it, results as follows:
Hooked it up to rail, 0 pressure
key on, pump relay kicks in 2 seconds pressure goes to around 10
off on, pressure climbs to 15-20
off on, pressure to around 30 it will start no problem there
Running with pressure regulator (I just changed that as well) connected to vacum around 38 and holds steady
Running with regulator unplugged 45, runs fine.
Shut off engine and the pressure drops to 0 in about a minute with the regulator was hooked up, with regulator unhooked it was running at 45 it will hold the pressure at about 45, very strange.
What would cause the pressure to drop to 0 all the time, think I have a defective check valve in the new pump? Can't see or smell any gas leaks. Van runs great, it has pleanty of zip, just that hard starting thing.
I also replaced the pump and PCM relays in the fuse panel.
Hi I would have to agree you have a bad check valve the pressure should remain there sometimes when you do the right thing. Things still go bad. I would get that pump warranty and replace it.
February, 28, 2012 AT 6:38 PM
Ouch, that thing is such a PIA to get out. Looks like I have a warm day project coming. I am going to check one more time for any signs of gas or smell, but suspect that is not the case. I do remember years back changing the fuel filter and the van was sitting for a good while, I had to releave the pressure at the mainfold first and there was pleanty there.
Thanks for you prompt response,
Appreciate the feedback
February, 28, 2012 AT 10:26 PM
Yes check all fitting and connections and if no leaks has to be the pump. Unfortuneately a leaky injector can cause this too maybe you will want to pull injector rail and injectors check for wet injectors this is hard to find since the fuel would burn up as soon as cyl fired. Just an idea. Good luck
February, 29, 2012 AT 2:37 AM
OK, and again thanks much. I'll let you know the solution.
February, 29, 2012 AT 11:52 PM
YES WE ARE ALWAYS HERE IF YOU DON'T FIND IT LET U KNOW WE WILL FIND IT
March, 18, 2012 AT 1:11 PM
UPDATE: OK, I did the new fuel pump yesterday, got an RMA replacement for another Motorcraft one and when installed I hooked up the pressure gage to the fuel rail, key on-off twice and pressure went right up to 35, turn the key and the van fired right up! Starts at like 45, the regulator takes it back to around 35 at idle and she holds steady, turn off it creeps down to 25-30, but holds. Bleed the pressure to zero, turn key it immeditley goes back to 40 within the 3 second intialization period. Seems to be working fine. I have never experience anything like this before when buying brand new OEM parts. Old one was defective. Not much in it, but like you said the valve must be bad.
Thanks for the assistance once again. You guys are great!
March, 19, 2012 AT 12:10 AM
Glad to hear it. We are here to help anytime.
May, 15, 2012 AT 2:15 AM
Hi, I havce the same problem again. The proble is a little differnt now. Goes for a while then it will do it a few times, have to on off the key2 times to build the pressure, then it fires right up. This is madning. Another bad pump? Leaky injectors? Van runs great otherwise, has like 115k on it and the motor screams. Any ideas would be really appriciated.