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Discussion Starter #1
Does anyone here have any ideas on how to check the fuel pressure on a 5.7 ('06)? I can't find a port anywhere, and the manual makes no mention of it but does list Mopar 6631 and/or 6539 as special tools which look to me like they add a temporary port in line so you can test.
A stuck open fuel pump check valve is the only thing I can think of that would explain my symptoms but it sure would be nice to do what should be a quick and cheap fuel pressure test before dropping $240 on a fuel pump that may not be needed.
FWIW, symptoms are:
Engines cranks good and strong but won't start
On 2nd try it sputters a bit and sometimes starts, sometimes doesn't.
3rd try fires up every time like normal.
If I don't crank but just turn the key on for a few seconds, then off, on, off, and crank then it always fires right up also (i.e. what I think I am doing is priming the pump to build up pressure).
No codes have been thrown, and this happens whether it has been of for a minute for a day, hot or cold, etc.

In the meantime I dumped a bottle of fuel system cleaner in the tank hoping for some magic to happen.
 

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Sound

Can you hear the fuel pump when you just turn the key on? as it sounds like the check valve also, but if you have a broken wire or a bad connection and the pump is not the getting power all the time it may have similar symptoms.


Swanny
 

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Discussion Starter #3
I can't hear it at all from the driver's seat. I need to put my ear on the fill hole when my wife gets home to turn it on for me.
 

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What happens if you park the vehicle in the "Nose up" position. I mean a position where the front part of the truck is higher than the rear? And what in the opposite case? Will it start faster?
 

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Discussion Starter #5
I never did get the fuel pressure tested - I was going to disconnect where the fuel line connects to the fuel rail and test there but I couldn't get the line disconnected. I ended up just replacing the fuel pump and it fixed it. Due to the symptoms I was having I was unable to use the depressurization procedure but when I disconnected the lines at the pump there was no pressure anyhow, so I think it had to have been the check valve.
 
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