No Power to new fuel pump
February 15th, 2016, 8:28 PM
#1
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No Power to new fuel pump
I have a 2000 Express Conversion van , 5.7 engine m 154000
Fuel pump went out when I was out of town last August 21, got towed in to a shop , they replaced fuel pump , van started and ran , started home and after about a 100 , miles check engine light came on , the code was for low pressure , advance auto had sent the wrong fuel pump , Drove back to shop 90 miles and they replaced fuel pump with correct one on August 21 , Van ran great for two months it just died going down the road , had it towed,. pump will not run back home come to find out ECM fuse had blown , replaced fuse , van ran fine for a few week , Two more times it has died , when it wont start cant hear fuel pump running ? Last time Week ago , I dropped the fuel tank and got a replacement puimp as Advance has life time warrenty , Installed pump , pump wont run ,
Checked fuses , voltage 12.3 volts , checked relay , installed a new one and can feel it click .
At fuel tank harness , I get 12.3 volts for 2 seconds , then when engine cranks , voltage drop to 10.9 volts , release starter , voltage jumps up to 12.3 for 2 seconds .
Dropped tank and checked voltage at tank , none WTF !!
Should volage drop to 10-11 volts to pump when engine turns over ???
I pulled the tank wireing harness and check continuity and both grey wiire and black wire show continuity ... yet the pump will not run !!
I am at a loss what to check next ???
Any suggestions Thank you in advance !
Fuel pump went out when I was out of town last August 21, got towed in to a shop , they replaced fuel pump , van started and ran , started home and after about a 100 , miles check engine light came on , the code was for low pressure , advance auto had sent the wrong fuel pump , Drove back to shop 90 miles and they replaced fuel pump with correct one on August 21 , Van ran great for two months it just died going down the road , had it towed,. pump will not run back home come to find out ECM fuse had blown , replaced fuse , van ran fine for a few week , Two more times it has died , when it wont start cant hear fuel pump running ? Last time Week ago , I dropped the fuel tank and got a replacement puimp as Advance has life time warrenty , Installed pump , pump wont run ,
Checked fuses , voltage 12.3 volts , checked relay , installed a new one and can feel it click .
At fuel tank harness , I get 12.3 volts for 2 seconds , then when engine cranks , voltage drop to 10.9 volts , release starter , voltage jumps up to 12.3 for 2 seconds .
Dropped tank and checked voltage at tank , none WTF !!
Should volage drop to 10-11 volts to pump when engine turns over ???
I pulled the tank wireing harness and check continuity and both grey wiire and black wire show continuity ... yet the pump will not run !!
I am at a loss what to check next ???
Any suggestions Thank you in advance !
February 17th, 2016, 3:25 AM
#3
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UPDATE , Got my neighbor to come over and he brought his power probe . What we found was the main plug from engine harness to fuel tank harness both the ground and hot wire were not making a good connection !! We bent the tabs inside the engine harness plug slightly till we were making a good contact and we could wiggle it all around and not lose either the ground or power .
It all makes sense now as to why it would run fine then die , then run again !
I will buy myself a power probe !!!!
It all makes sense now as to why it would run fine then die , then run again !
I will buy myself a power probe !!!!
February 17th, 2016, 1:54 PM
#4
a lot gm models require an updated harness connector when replacing the pump. the connector pns make intermittent contact and burns the connector.
get tne pp3, its way better than the first two versions. it is a very good tool.
get tne pp3, its way better than the first two versions. it is a very good tool.
