Can't get power to the fuel pump

I have a 2000 toyota tundra I can't keep running someone bypassed a fuse under the hood to get it running, now I am not getting any power to the fuel pump what do I look for to find out why the fuel pump.to come on I have checked all the fuses

 

Look for the resistor on the drivers fender. Disconnect it and jump the terminals.

 

Do you know what fuse they bypassed ?

Fuses under the hood ? Physically and/or with a volt ohm meter(VOM) ?

You measured for voltage at the fuel pump ?

You did indeed checked EFI fuse underhood ?
Can someone help you check the EFI relay by you placing finger on top of EFI relay while they crank. Did you feel the relay energizing or follow the below PDF to check relay with a VOM.

 

Which terminals do I jump? I will look at it see how many wires go into resistor thanks for the advice.

 

It was the main EFI Looks like there was some kind of metal shoved down into the terminal where the fuse plugs in also the other side of was broke off looks like maybe a wire was disconnected

 

So if I disconnect the resistor and jump the wires, should I hear the fuel pump come on, if it does, it means the resistor is bad? It is a new fuel pump I just replaced it, but when I turned the key there was no power to the fuel pump.

 

MMM. Bad fuel ECU, if you jump it, it should come on, if it doesn't you may need to probe the power from the ECM itself....
If you jump it make sure it's a thick enough wire to take the voltage.. I jumped my car's harness with too thin of a wire and it fried it and I was stranded..

 

As in you were attempting to crank it ?
Reason I ask is because voltage will only be at the pump with engine cranking. IGN ON only gives it power for 1 second. If the ECU doesn't see a crank sensor rpm signal, it cuts power to the pump.

Things you gotta have besides pump EFI relay, Circuit opening relay(C/OPN next to EFI relay), Crank Shaft Position Sensor, EFI fuse and few other things can't remember.

Well that doesn't sound good. Possibly take a pic of what you are seeing ?

Being a resistor, there are 2 terminals !

 

No fuel ECM on the first gen trucks.

 

It may be the fuel pump resistor posted above. Lexus calls it the Fuel ECU, its the exact same thing... I've seen it, and played with it.

 

Any luck with this??

 

Aside from that, check for voltage at the fuel pump relay socket. If you have no power there, there's no way to send power to the fuel pump.

Cross your fingers and pray to your deity a previous owner didn't install an aftermarket store-brand fuel pump because most of those die within 2-4 years of use.

 

Hey guys. I just put in a new fuel pump on my 4.7 limited edition. Pulled the box off to do the operation. bench tested the pump, works .
installed it. Truck turns over but doesn’t start. Checked all my relays and fuses. Jumped the resister, still nothing. Took the connector off the top of the pump and connected 12v directly to the pump, truck starts up and runs perfectly….
Reconnected the connector, still won’t fire!
Any suggestions?

 

Any codes? Crank position sensor and temperature sensors not working will prevent the fuel pump from getting power.

 

I don’t have a scanner….

 

Is the check engine light on?

 

I didn’t look while I had it running . I will do that tomorrow. Thx for asking a good question

 

I presume you installed it properly, and removed the negative battery cable BEFORE you started the process, to avoid creating sparks that could quietly pop fuses?

If not, did you check all the fuses, including the EFI1 / EFI2 or whatever in the engine bay, including the window fuses? I can't recall what all fuses are in the fuel pump circuit, but I would check them all. Did you check all fuses in the dash?

Just because a fuel pump worked on the bench doesn't mean it'll work in the tank. If you bought store-brand or scAmazon/fleaBay parts, we've had more people come here with problems after installing aftermarket parts which were DOA or died same-day/same-week/same-month between the fuel pump and starter that it's almost an inside joke at this point. Parts store/aftermarket quality is utter, horrific shit these days.

 

Yes the install process was “on the up”. I checked the pump several times throughout the process also, works every time by direct connection. It’s an OEM part too. .
wont make that mistake. I will see tomorrow what’s on the for dash lights…..

 

Well I bought a scanner. Lots of codes! P2135 throttle position sensor is the first one. But when I connect direct 12 V to the fuel pump, the truck runs fine. Head scratch for sure!

 

Sounds like you may have an electrical gremlin/short. What are the other codes?

 

Great. P0121 P0123

 

Well, that explains a lot. Note the fail-safe operation associated with those codes, from the everyone-can-download-this-manual-freely FSM which is linked in our community megathread.

​

Are you saying this all existed BEFORE the fuel pump install, or IT EXISTED BEFORE AND AFTER?

Did you happen to spray anything liquid into the throttle body, by chance, while cleaning it or something? If yes, please tell more. What was it, and how much did you spray in there?

Did you do any other work just before this started?

I'd be inspecting this specific connection is secure on the throttle body and can't be pulled off, i.e. it's snapped in, not broken, none of the wires are loose when jiggled. I'd be tracing its wiring harback the wiring to see it's intact. I'd be checking fuses, but without digging into the electrical wiring diagrams (EWD), I can't say for certain which fuses you'd want to check. It's easy enough to test all the fuses up under the dash, and not too bad to do all under the hood.

​

 

I bought the truck a couple weeks ago and took the guys word at face value that the fuel pump was gone. I took the box off, changed the fuel pump to an oem one, but tested both on the bench. The seller was correct. The old one didn’t work, and the ‘new’ one did. (Got it from a car parts place down the road from me)
The seller informed me before I bought the truck that he sprayed ether down the intake. No idea if that’s true or not. Or what he sprayed. But the throttle position sensor seems like a good bet. It made a weird noise when the key is in the on position. So I unplugged it, plugged it back in, and the noise stopped, but still, no start. Just ordered one. Arrives tomorrow. Gonna try that. For 100$ can’t complain….

 

Well I installed a brand new throttle body, still doesn’t start. So I took the connector off the fuel pump, and connected 12v directly, and the truck fired right up with no lights on the dash. Ran it for about 10 seconds. Ran perfectly. Then I re- connected the connector again on top of the fuel pump, wouldn’t start……

 

Sounds like the harness isn’t receiving 12v because the computer doesn’t think everything is ready. Still no codes with the new TPS installed?

 

Same codes as before….

 

Then the real problem still exists