No Power to Fuel Pump After Engine Swap

So my truck is a 2003 3.4L MT and I just swapped in an engine from a 2001 3.4L MT with the 2001 ECM and it cranks but won't start. I have gone through the below steps to narrow it down to no voltage supply to the fuel pump but I don't know where to go from here.

First thing I did was swap the crank sensor, plugs and coils from my old engine which I know were good. Then I sprayed the MAF sensor with some MAF cleaner. Still cranks but won't start.

Second thing I did was check the EFI fuse and that was good. I then popped the intake off the throttle body and sprayed some fuel in there, reconnected everything and when I cranked the engine it tried to start. I then disconnect the fuel supply line in the engine bay and got nothing coming out when it was cranking.

Third thing I did was take the wiring connector off the fuel pump and supplied voltage directly to the fuel pump and it works. I then put a voltmeter on the wiring connector and got 0 volts when cranking. I also swapped the fuel circuit opening relay just to be sure but still nothing.

 

The fuel pump will not be commanded on until it sees an RPM signal.
It would be super helpful if you had a scan tool to monitor data while cranking.

But you can also see if the tachometer moves while cranking?
Does the tach move when cranking?

When need to start somewhere. Start there.

I also understand you swapped the crank sensor. But that doesn't mean much.
We need some more data.

 

You can also check the 7.5A Ignition fuse too.
It cost nothing to check, and it plays a role in powering the fuel pump.

 

I do have an ultragauge but it will not connector after swapping in the 2001 ECM. I don't get any rpm reading on the dash while cranking but when I sprayed some fuel into the throttle body and it fired for a second I did get rpm.

 

Interesting....

I think I seen that the DLC connector (OBD plug) had a power feed from on on the relays associated with the EFI or Fuel pump Relay.

Let me check.....

 

Do you have a voltage meter or test light?
You are going to need on to further test things.

 

We need to make sure the crank sensor is plugged in, and has a good connection to the ECM.
Until we get a crank signal, we are at a stand still.

 

If you or anyone else would like to follow along, or help, see the Engine Control diagram below.

http://www.markofshame.com/fsm/03_Tacoma/Wiring_Manual/03tacoma/systemci/017ecs5v.pdf

 

Does the Check Engine light illuminate when you turn the key to the ON position?

 

I don't remember but I'll check tonight.

 

I got busy and am now back to messing with the truck. Check Engine light is not on and I checked power at the EFI relay and I am getting 12V.

 

Both crank sensors i have tested at 1.9k ohms which i believe is in spec. The wiring connector at the sensor looked good. No obvious damage to the pins.

 

If the CEL is not on in the ON position, than the ECM is offline.
We need to check powers and ground to the ECM.

 

The most common failure point is/are the ECU grounds near the DIAGNOSE plug on the upper intake driverside. You should see a group of wires to an eyelet.

 

So if I swap in my original 2003 ECM and the CEL is on with the key in the ON position, then the 2001 ECM that came with the engine is bad? Or is there a way to bench test the ECM to confirm?

 

It's worth a try.
But I'd want to make sure the pinout is the same for both.
Just because I'm "that way".

I'd hate to dead short an ECM. But, generally, that doesn't happen.

Anyways, to answer the question.
Yes, you can do that. I the CEL comes on. The ECM is online.
And your scan tool should connect.

All that said, I'm still leaning towards a power/ground issue.
But swapping the ECM is not a "bad" idea. Try it an see....

 

Well I put in the "old" 2003 ECM and the CEL comes on and I get voltage to the fuel pump when cranking. Is my best option swapping over the 2003 throttle body and wiring harness onto the "new" 2001 engine?

 

Yeah. You need to use the original harness.

 

With just my luck swapping the engine harness, intake manifold and throttle body worked. BUT something went wrong with the clutch while installing the engine and it is acting like the clutch is engaged all the time. So the truck now runs but it won't move.

 

Can you shift between gears with the motor off? Does the clutch "feel" normal as far as throw goes?