I hope it is the fuel pump

[96DiscoSE7]

yesterday morning came out and truck just cranks and cranks, finally starts, went to work and in the afternoon does the same thing, part way home just dies. Towed back home and when I went to remove the lines there was just a dribble of fuel out the lines.
also noticed in the past few weeks that there was a slight hesitation while driving along the hiway, very slight. new pump should be here in the morning.....:banghead:

 

[Chris-St Louis]

Did you confirm voltage at the pump?

 

[junkyarddisco]

filter?

 

[peter sherman]

Did you confirm voltage at the pump?

What he said
http://discoweb.org/forums/showthread.php?t=14451

 

[Lake_Bueller]

After confirming voltage at the exterior plug, then check voltage at the interior plug.

My fuel pump finally bit the dust on Friday. In hindsight, I think it's been slowing dying. The write-up that Peter posted is excellent. I didn't have the fortune of computer access when mine died. But a 5 minute phone call to Muskyman answered all the questions. Once I removed the pump, it was a extremely simple swap.

BTW....I went with the E3270 pump from Advanced Auto. Don't forget the new sock, fuel hose and clamps. READ the whole post for some pointers on installing the hose clamps. My total for all parts was just under $100.

 

[roverboy03]

like they said check voltage to the pump....and clean your MAF just in case...mine did the same thing....it was my MAF.....after i bought a new fuel pump

 

[roverMc]

Did you hear the pump spin up? If so change the filter.

 

[Lake_Bueller]

Just because the pump "spins up", it doesn't mean that it's good. Mine got to the point were it would spin when it was in the mood.

Perfect example...when my truck died on Friday, the first thing I did was listen for the pump. No spin. Okay...check voltage. That was fine. Pull the pump and test voltage at interior plug. Also fine. Replugged and for shits & grins, had a buddy turn the key. Motor spun. Reinstalled and the damn thing didn't spin. Installed new pump and no it runs like a champ.

BTW....it's not the first time I've had a 'no start' issue.

 

[roverMc]

Just because the pump "spins up", it doesn't mean that it's good. Mine got to the point were it would spin when it was in the mood.

Perfect example...when my truck died on Friday, the first thing I did was listen for the pump. No spin. Okay...check voltage. That was fine. Pull the pump and test voltage at interior plug. Also fine. Replugged and for shits & grins, had a buddy turn the key. Motor spun. Reinstalled and the damn thing didn't spin. Installed new pump and no it runs like a champ.

BTW....it's not the first time I've had a 'no start' issue.

Agree, but the filter's easier and cheaper to start with.

BTW - Like the new avitar!

 

[96DiscoSE7]

Well it is not just the fuel pump....... the old one sounds weak compared to the new one, so I am ok with that purchase BUT now I am not getting the test light to light for the 5 or so seconds at the wire harness, I pulled the short harness out and have no resistance there, testing at the harness at the frame gives no light while testing the purple/white wire..... I am going to bed to start fresh in the morning........:banghead:

 

[MUSKYMAN]

Well it is not just the fuel pump....... the old one sounds weak compared to the new one, so I am ok with that purchase BUT now I am not getting the test light to light for the 5 or so seconds at the wire harness, I pulled the short harness out and have no resistance there, testing at the harness at the frame gives no light while testing the purple/white wire..... I am going to bed to start fresh in the morning........:banghead:

remember that it activates the pump for 5-10 seconds and then cuts the voltage

voltage only comes back when you start cranking.

 

[MUSKYMAN]

Agree, but the filter's easier and cheaper to start with.

yeah the filter is easy...LOL

keep telling yourself that:rofl:

 

[96DiscoSE7]

remember that it activates the pump for 5-10 seconds and then cuts the voltage

voltage only comes back when you start cranking.

sometimes I had light for 5 seconds, sometimes nothing.....
now onto the relay box at the front fender, in that there are three relays on the PC board
with no test light i can still hear a relay click off after the 5 seconds, but tonight I need to see/hear if more than one relay clicks on/off with or with out test light lighting.... -Andy

 

[Lake_Bueller]

yeah the filter is easy...LOL

keep telling yourself that:rofl:

That's because "easy" is a relative term. I've found the biggest problem is the need for a third hand:smilelol:. Once you get that problem solved, it only takes about 30-40 minutes.

 

[peter sherman]

That's because "easy" is a relative term. I've found the biggest problem is the need for a third hand:smilelol:. Once you get that problem solved, it only takes about 30-40 minutes.

LOL!!!!!
For me 20 min or Pulp Fiction!! Anyway its gonna come off........
Just fill every cranny with antiseize on assembly

 

[96DiscoSE7]

well at least now there is no voltage at the pump, but still one relay closes for the 5 seconds to run the pump when the key is set to the run position..... I think the main relay in the box is next area to look at....

 

[96DiscoSE7]

Did you confirm voltage at the pump?

see above...

 

[96DiscoSE7]

still no voltage at the pump, but the sending unit works fine, got voltage at 15A fuse, and on both wires [ purple/white] coming out of the realy box, once relay closes after 5 seconds then the second voltage reading drops to 0..... I did find some bad crimp connectors in the rear, really thought that was it [ it would have been in short time with out rectification ....... I am getting better at using the multi meter..... any insight is welcome -Andy