Swapped in 5.0 wont' start

[Jeepin5.0]

In the middle of swaping in a 91 5.0 into my Jeep.
The engine will crank all day, but won't fire. If i use starting fluid it will cough for about 3 seconds. It is getitng fuel.
I do not have the O2 senesors, alt or power steering connected yet, but was told that wouldnt' keep it from starting.
I have verified spark.
Compression is good.
I have been told that all vacuum ports must be either connected or plugged on the intake manifold in order for it to start. I have them connected and plugged.
Is there a vacuum port on the fuel rail anywhere that needs to be connected?
Timing was set correctly, but i might have changed it a little bit trying to get it to start.
Are there any electrical connections that would keep it from running?
Also, I do not have anything smog related hooked up, and dont ahve the ports in the rear of the block plugged yet, but have been told this won't affect the starting either.
I'm getting really frustrated. If you guys know of any message boards/people/garages or clubs in se pa, that would be a great help too.
Thanks
Josh

[lx5091]

that's really a tough call, as you understand that it's not easy to troubleshoot an engine problem when it isn't in it's normal environment. Props to you though, glad to see someone not using a Chevy 350 for the swap! If i had to hazzard a guess it would be a fuel problem, you really need to verify pressure and if gas is getting there. Spark management would be my only other suggestion, but I really think it's fuel related.

you didn't mention too much about what you checked regarding if you're getting fuel...can you get a guage in there somehow. How are you feeding it? what type of pump are you using?

[Jeepin5.0]

I'm running the fuel pump setup for a frd truck witha efi 302. It includes a low pressure fuel pump to draw fuel from the tank, and then feeds to a high pressure fuel pump, also for a truck. I know the rails are getting fuel, but i'm still going to have to chekc the pressure. What is the ideal pressure I'm looking for? The engine is mostly stock right now
Thanks
Josh

[Kevin Price]

Are you using a fuel relay? This is usually found under the passenger side seat. We swapped a 5.0 into a 64' Ford truck and we had fits too. If you dont have one get one at a salvage and review the wiring from a Chiltons to see how it wires to the computer. The computer needs this to work.

Gosh, I'm trying to remember. Seems like on the stock a harness there is a piece used to plug diagnostics into, its a small wire connection that has a cap on it with 2 ports. With the key on you should be able to cross these two over using a wire. If everything is working you should hear a series of clicks. With the stock harness it on the drivers side portion

From here, you'll HAVE to have a Chiltons and (the other manual) and strat tracing the wires from the computers. It is a bit intimidating at first but its not too bad.

[bigred90gt]

I havent really dealt much with fuel delivery, but I think there is a vacuum line that is supposed to hook up to the fuel pressure regulator. I think the stock setting for fuel pressure is 38 psi. Someone correct me if I'm wrong. Good luck with it. Sounds like an awsome project.
Caymon

[Jeepin5.0]

I am not running the fuel pumps through the fuel relay. The fuel pumps are run off a normal toggle swtich. This could be the problem, but if the fuel relay would keep it from starting, why would the engine crank?
Hopefully there is a vacuum port n the regulator.
Can anyone verify that ALL vacuum ports must be connected or plugged in order for it to fire?
Also, I do not have the check engine light plugged in yet, nor the o2 sensors
Thanks for all your help.
Josh

[Kevin Price]

Vacuum has nothing to do with your problem, it does have an effect under full throttle as it closes the regulator.

The computer does not know the fuel pump is on without the relay telling it it is on. Therefore, if your computer thinks your fuel pump is off it will not fire the injectors. So, your engine will crank all day, its just not going to be getting any fuel.

Your fuel pumps don't necessarily have to run through the relay, you just have to close the circuit so your computer thinks it is running through the relay. Get a relay from a mustang in salvage, trace the wiring from the computer to the relay and I bet you money she'll fire right up.

[Hethj7]

If you believe you are getting spark and fuel, are you sure your firing order is correct? I know when I did my engine swap, I had the same problem. Turned out I hadn't paid enough attention to the firing order. Hopefully it your problem may be something simple like this. Good luck!

[Jeepin5.0]

Kevin, that sounds like a very good answer. i'll try that tomorrow. I think i can just cross the two hot wires rather than getting a relay. I don't think i'd find much in the yards under the 2ft of snow we have.
My only question concerning the relay is that when i put starting fluid in, it will fire for 2-3 seconds. How can that be explained in relation to the fuel pump relay.
Thanks to all of you guys for your help.
Josh

[Kevin Price]

I assume you are putting starter fluid directly into the cylinders via the spark plug hole. Given this, the spark from the plugs is igniting the starter fluid. However, since your computer is not telling your injectors to "squirt fuel" it will run just long enough to burn the starter fluid.

Also, should you need the relay you can call Mustang Parts Specialties in Winder, Georgia. They'll have what you need. Let us know how it goes.

[Jeepin5.0]

Ok found the problem, which is what you guys were saying from the start...the injector was not firing. Now we think it might be a problem with the comp. Its being tested tomorrow. Hopefully if thats the problem, when i get a new one, it'll fire right up.....hopefully....
Josh