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Discussion Starter #1
Ok guys i know this is pretty general to start with but i am not sure where to start with all of this. I was just driving down the road and the truck dies. I have spark, but no fuel pressure. I have a brand new fuel pump, and can hear it running but no pressure at the rail. after sitting a while i have pressure again, but still wont start. after very extended cranking at starts but lopes like a have a huge cam in it and very high compression. I unplugged the IAC to see if that was causing the issue with no change other than to just die completely and not start back up. when i had it running i attempted to frive it back home ( about 8 miles ) and the trans is in safe mode. Over drive light flashing, trans holding gears until i completely let out of the throttle, and the engine running extremely rich to where it looks like a diesel driving down the road. I may be wrong in theinking this here but i am thinking that my computer is pretty much toast, and need to replace it. I tried to pull codes, but since this happened it will not flash the check engine light for codes, and afraid to drive it any further to get a scanner on it if it will even read codes on the scanner. What are any ones thoughts?

Thanks guys,
Dave
 

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If you hear the pump and you don't have pressure. Do you have fuel? Just because you hear the pump doesn't mean its pumping. You say if you let it sit a while you have pressure again. if you jump out the fuel pump so it runs continously do you have pressure while cranking?

edit: if you can't pull codes, check the eec relay.
 

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Discussion Starter #3
when i hear it running but have no pressure yes i have fuel, and the pump sounds like its just barely geting anough amperage to get the thing running.

i swapped out the EEC relay for a new trying to pull codes and still wont pull them


any other ideas?
 

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jump the fp at the relay and see if you have full fuel pressure...
If it sounds weak i'd start checking for voltage drops. Well actually i would check for voltage drop at the fuel pump and if it checks out i would jump the pump out and see if i had full fuel pressure. Remember it only takes one strand of wire to allow voltage to pass (12+ or -) but you can't flow the same amount of electrons across the same single strand. If you have a bad ground it could easily cause the problems you have considering if i remember correctly the fuel pump ground is up front by the ecm.
 

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Discussion Starter #5
its a rand new pump, and have voltage everywhere. only reason i m looking at computer is the way the tranny was being affected as well as the engine surging terribly
 

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Take it out, open it up and look for any burned sections.
 

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You have several issues pointing to low voltage or poor ground(s). One of the symptoms of not being able to pull codes is low battery voltage. You also stated "when i hear it running but have no pressure yes i have fuel, and the pump sounds like its just barely geting enough amperage to get the thing running" this also leads me to believe my theory of low voltage or a ground issue. If the starter cranks the engine with no problem I suspect a chassis ground problem.

Check the ground lead running from the negative battery terminal to the fender as well as the lead that runs to the frame then onto the engine block.
 

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Discussion Starter #8
ok i will double check all grounds again, but this was just all at once. have good voltage on everything it seems, but will double check again. any other ideas?
 

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I still think you have a voltage drop somewhere.
 
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