FORD TUFF

As per your memory code 542 ,,yes it might have been set because you tripped the inertia switch,,,,,Breaker or 10,, code splits the hard fault and memory fault codes,,,Your running codes 4,,1,,111 = 8 cyl,,,throttle test,,,system pass ,,Engine revving up is normal for running test,,,,,So everything is fine with your injection system at this time,,,, Check FUEL PRESSURE with a guage before going any further,,,

jonwon

how do you guys think shes running ?

im going to check fuel pressure with a guage like ford tuff said. any advice on checking fuel pressure ?

jonwon

hey guys , i checked my driveshaft ujoints and one of them has a half inch of play.. im concerned its about to give so i am changing both ujoints out tomorrow. can anyone give me a heads up on what i am up against ? i changed out two ujoints on a 94 f150 automatic last year. my new truck is a manual 5 speed. am i going to lose fluid ? any suggestions are appreciated , thanks!

Chris_1

iTrader: (1)

Pretty much the same as the automatic. You shouldn't lose fluid (unless you park it with the nose uphill maybe).

jonwon

thank you chris , i feel better

jonwon

so i changed out the bad ujoint and the truck rides so much better! thanks guys.. now i am going to buy a fuel pressure gauge to check my fuel pressure. can anyone tell me what i am looking for with that procedure ?

Chris_1

iTrader: (1)

There's a schrader valve on the fuel rail. Screw the gauge on that. Turn the key to on. You should be looking at 42 -43 psi. Let it sit for a few minutes and see if it holds pressure
Start the truck and let it idle. Pressure should drop while idling about 5 to 8 psi.
Open the throttle a little, pressure should climb back up to it's maximum - that drop and climb is the pressure regulator opening with high vacuum and closing as vacuum drops.
Disconnecting the vacuum hose and plugging it back in will do the same thing.
Also smell that vacuum hose for a fuel smell, which would indicate a leaky diaphragm.
Your truck runs between 30 to 45 psi. It doesn't run below 30

jonwon

thank you chris. you have been helping me a lot! youre my hERO
when you say disconnect the vacuum hose and smell it are you talking about the break booster vacuum hose ?

Chris_1

iTrader: (1)

No, the little vacuum hose that goes on the fuel pressure regulator to operate it. When you have high vacuum from closed throttle plates (idle or foot off and coasting) the regulator opens to lower fuel pressure. That provides a little gentler spray out of the injectors when the air isn't barreling past them.
The regulator is at the other end of the fuel rail (back). It's the big round thing with a vacuum hose on it.
It can stick open or closed, or the rubber diaphragm inside can start to leak, which allows fuel to pour into the intake through the vacuum line.

jonwon

i connected the fuel pressure gauge to the schrader vavle on the fuel rail at that time it read about 5 psi. i whent key on engine off and the fuel pressure rose to about 30-35 psi. i whent key on engine on and the fuel pressure was at a steady 32-33 psi. i slightly opened throttle and the psi dropped to 32-29 psi. i turned off the engine and the fuel pressure rose to 40 psi. what does this mean ?