Fuel Pump Problems (1 Viewer)

[flip1000]

I can't get my 2000 Toyota Land Cruiser to start. Here are some details:
Ran fine, turned car off and then wouldn't start when I tried to turn back on 5 minutes later.
Turns over fine.
Runs fine on starting fluid.
Fuel Relay works checked good.
EFI fuse good.
I replaced fuel pump and still have problem.
When I run both the old and new fuel pump directly from battery they both work.
When I measure the voltage at the plug that attaches to the fuel pump assembly it goes to 10.5V when I turn the key on, but it won't run the pump. Battery is showing 11.8V on my meter.


This is not an immobilizer problem. I've been thru that issue and the flashing light on the dash is behaving appropriately.


My only thought is even though I'm getting 10.5 volts there is a fine crack in one of the fuses or relay that is not allowing any current draw? I know that's grasping at straws but that's where I'm at.


Any help would be greatly appreciated and I will be sure to post what the problem was when it's resolved.

 

[flip1000]

Additional comments:
I removed the EFI main relay and then used a wire to jump the terminals just to verify the relay wasn't the problem. That didn't make any different. When I jumpered the terminals I did hear something running right on top of the engine. Maybe something from the throttle body or the pulsation damper?


I measured the voltage at the pump with the pump connected. It showed 0 volts. Pump disconnected was 10.5 volts.


I changed the EFI fuse even though it checked good. Are there any other fuses that I should check? I have been thinking it wasn't wiring because it worked until I stopped and then didn't work when I tried to start it back up. One other comment is that this happened a few days after a cold snap ended here. It was -20F for a week or two, warmed up and then the issue popped up. Does anyone have a wiring diagram I could review?

 

[flip1000]

I paid $15 for two days access to the Toyota manuals and wiring diagrams. It was a broken -12Volt wire between the fuel pump ecu and the fuel pump. This is one of five wires that are tied together at a connector right beneath the drivers side rear seat. They were broken at the connector. A fuel gauge wire was broken too and my fuel gauge was working before it stopped. Maybe ice was hanging and broke the wires as I hit a bump before I stopped? There is a large dip I go into right before I park. Obviously I'm grasping at straws.


There is also a mystery of why I saw 10.5 Volts at the fuel pump. Maybe I was just looking from the +12 volt terminal and vehicle ground, but I don't think so. Maybe just one strand of the wire was touching at the break? Gremlin?

 

[MissoulaCruisa]

Can anyone help with part number for the electrical plug that powers the fuel pump? Plugs into the top of the fuel pump assembly? 1999 UZJ100 btw.

After replacing fuel pump twice, and the EFI fuse/relay, I finally discovered I've got a bad connection at this connector.

Can't find a part number though, #@& it!

Here's a pic from another thread ...

 

[flintknapper]

Part number should be on top of the connector. (11077) most likely.

Toyota part 90980-11077

Make certain you get your terminals pushed all the way into the new connector/housing and use some dielectric grease on the male tabs.

 

[Alirezakad]

I paid $15 for two days access to the Toyota manuals and wiring diagrams. It was a broken -12Volt wire between the fuel pump ecu and the fuel pump. This is one of five wires that are tied together at a connector right beneath the drivers side rear seat. They were broken at the connector. A fuel gauge wire was broken too and my fuel gauge was working before it stopped. Maybe ice was hanging and broke the wires as I hit a bump before I stopped? There is a large dip I go into right before I park. Obviously I'm grasping at straws.


There is also a mystery of why I saw 10.5 Volts at the fuel pump. Maybe I was just looking from the +12 volt terminal and vehicle ground, but I don't think so. Maybe just one strand of the wire was touching at the break? Gremlin?

I can't get my 2000 Toyota Land Cruiser to start. Here are some details:
Ran fine, turned car off and then wouldn't start when I tried to turn back on 5 minutes later.
Turns over fine.
Runs fine on starting fluid.
Fuel Relay works checked good.
EFI fuse good.
I replaced fuel pump and still have problem.
When I run both the old and new fuel pump directly from battery they both work.
When I measure the voltage at the plug that attaches to the fuel pump assembly it goes to 10.5V when I turn the key on, but it won't run the pump. Battery is showing 11.8V on my meter.


This is not an immobilizer problem. I've been thru that issue and the flashing light on the dash is behaving appropriately.


My only thought is even though I'm getting 10.5 volts there is a fine crack in one of the fuses or relay that is not allowing any current draw? I know that's grasping at straws but that's where I'm at.


Any help would be greatly appreciated and I will be sure to post what the problem was when it's resolved.

Hello flip!

Is your problem solved?
What is the voltage after you fixed the brpken wire?

Can u adress the exact location of the connector? Would be much better if u could share some photos of it
Tnx

 

[Cantatan]

I think I have the same problem. Will report back once I have done further diagnosis

 

[hickuptruck]

Yes, I had same problem. It is intermittent. Comes once or twice a month. Its pointing to I need a new fuse box, or the EFI fuse fix from a ih8mud member here.

 

[ramangain]

Two more things to always check with these crank no start situations ...

1. Check all ground, especially those connecting block to chassis
2. Crank position sensors start to go wonky, and replacing has been known to solve the issue. The CPS can cause the intermittent issue

 

[ramangain]

Someone (Paul?) should write a "crank no start" diagnosis thread with step-by-step direction of what to check, in what order. Great for the archives.