Truck cranks but will not start [Solved].

My wife isn't here to crank it to test. I can use a test light and jump the control wire on the plug right? Do you know which wire that is on the plugs?

Also, what would be the best way to test for fuel without a fuel pressure tester?

 

No, the coils are controlled by a 4 volt pulse from the PCM and they send back a 5 volt pulse as a confirmation.
Shoot a bit of carb cleaner down the intake and see if it trys to run on that, if it does then most likely you have good spark and we are missing fuel.

About all you can do is take the line off here, put a piece of hose on the fitting on the frame, run it into a container, and see if fuel comes out when you crank on it.

 

Okay she started with starter fluid. Im wondering if the fuel pump hose routing in correct. I have it just like that unless theyre suppose to cross. When I disconnect the driver-side fitting fuel sprays everywhere

 

I thought they were different sizes so that they couldn't be mixed up, do you have fuel at the line I showed above in the engine bay?

 

Yes, I disconnected it and nothing came out. The pump is definitely priming. Looking at my pictures and then the tape marks on the hoses on the fuel tank, it seems I swapped the hoses in the wrong spot

 

Ah well that would seem to be the case then if you have no fuel at the engine but do at the tank unless something got pinched, that's interesting just about everything has 2 different size lines.

 

Got it! I swapped the front two lines and it runs!! Thank you so much!!

 

Correct, the fittings under the truck have different line sizes but it's the same connection on the fuel pump cap. And apparently, the front has the same connections!!!!

 

Nice, so this problem was "built in".
The original problem was a bad main relay.

 

I knew the 4cyl had the same sizes at the engine because people get them mixed up when removing the intake manifold but I was thinking they were different sizes on the V6.

 

Well, thank you for everything! I want to make something custom for you and @TnShooter. I will DM you guys and we'll figure out something to make you!!

 

Good to hear.
I’m like @Dm93 and thought the 4.0 use 2 different dive lines? We have see people get the lines swapped on the 2.7.
I learned 2 things from this.

1. if the correct powers are not seen at the ECM, it kills the 5v reference.

2. The fuel line sizes are the same. Mark them if you disconnect them. Electrical tape, zip-tie ect.

 

The sad part is I did zip-tie them lol.

The lines are the same size on the fuel pump cap but under the truck connections are different. I couldn't get them to connect, so I think they have to be different.

 

Well done mate

 

Now thats it's fixed you may want to edit your title to add (fixed) or (solved) so it may be useful to others someday.

 

Will do! Put everything back together and she runs good!!. CEL is on and this fault came up.

 

Well crap, that likely means your critters were under the lower intake in the valley of the engine munching on the knock sensor wires as well.

 

Let’s hope not, that’s a BIG job.
The ECM will eventually set the timing to max retard.
You’ll notice a difference, it won’t have near the power it should.

 

Not a surprise if you had critter damage elsewhere.. they love those knock sensor wires

 

I drove my truck around it's running just fine. It definitely has power. Is this something I can check on the ECM?