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Well I have about 48 hours into trying to get my motor started. It turns over great, but won't fire. I posted on RRORC the same thing and got some good ideas, but nothing has worked. I have even had a Ford Tech come by with the shop computor and tester, with no luck. All the grounds, and wireing seem to check out. Have 55 pounds pressure at the fuel regulator. The injectors are pulsating, and the plugs are fireing. One person thought maby the injectors were not spraying. The motor did sit for over three months on the garage floor, but I don't see how they could get plug up just sitting there. But its the only thing I haven't tried yet. So I will take each one out and test it. Any ideas guys??

Back to the basics.

Air
Fuel
compression
fire

We'll assume compression is good

Pull a plug wire and check for spark

If you have spark, give it shot of starting fluid...anything happen?

If you have compression, fuel, and spark, then you're looking at an ignition timing problem. Is your dizzy 180 out?

I took a plug out and cranked it over for a few secondes, and yellow and blue spark showed up strong. Now I know that blue spark is the right color,and yellow indeciates a bad ground. But I have checked and rechecked ever ground in the sytem. The PMC,and ICM seem to be working correctly. Thanks for the ideas thou.

O.K., I give up, whats a dizzy 180?

Sounds like your spark is fine.

Dizzy = Distributor

A common mistake is people get it 180 degrees out because they mistake TDC for the top of the exhaust stroke.

Now that you know you have spark. Shoot some starting fluid down the intake. If it fires, you know you're looking at a fuel issue and we can go from there.

What motor are we talking about? 4.0L?

if its a 4.0L there is no distributer, it is a DIS system. also if it is a 4.0L you don't have enough fuel pressure. 80-100 is what you need.

I guess that rules out the distributor...... Starting to look like fuel problem.

So what are some reasons for low fuel pressure?

Are you using the factory tank and frame mounted fuel pump?

I think its in the fuel system also. I have a fuel cell, with a Holly 60 psi. pump. Been useing it for 3 years now. Sprayed starter fluid into the intake, and the motor fired. I know the injectors are getting a signal to fire, but no fuel is comeing out. I talked to a injector rebuilder today, and he was tell me that the neddle can rust shut in the injector if there was any water in the fuel when it set in the garage for 3 months. So I have pulled all the injectors, and will have them flow tested. They have 200,000 miles on them any way. I can only hope that this will get the motor running when I put them back in. I put an inline fuel pressure gauge in, and have 55pds. pressure to the regulator. Thanks for your ideas. I will post after monday when I get them back in.

I can see maybe one injector screwing up on you, but not all of them.

No, you're problem is mostly likely something very simple. At least you confirmed it's a fuel problem.

Dbrown says you don't have enough fuel pressure..... are you using the factory frame mounted fuel pump along with the in tank pump?

the factory pumps for the 2.9L will work. when I did my swap I just spliced the lines together. I checked autozone and they printed out the specs. the 2.9L is 5 psi higher on the lower number and matches that same high number so it works.

my b2 with an injected 5.0 sat for a long time, fired right up, then a day later, wouldnt fire, ended up that all the injectors werent working. they would get the signal, but the injectors were froze...


good luck

Well just have to wait and see what happens when I put them back in. For 3 years now, I have used only the Holly fuel pump. (60psi) I really don't think I have a pressure problem. Got the roll bar tacked in for welding, as soon as I can drive it over to the guys house thats going to weld it up for me. Got to admit, 40 years doing mechanical work, and I have never run into any thing like this problem. But, with all the GOOD ideas every one is giveing me, it will run again very SOON.

Well, wilbers post should be encouraging. You're almost there now! Make sure you give us a report on whether that was the problem or not.

I just can't imagine why the injectors would plug up though. A car should be able to sit without that happening. Wonder if it has to do with shitty gas.

I know this may sound stupid, but did you replace the fuel filter?

I wonder if having too little fuel pressure allowed the injectors to build up gunk.....or if you had more fuel pressure, they would have been able self clean.

see, thats the thing. I was told that the 4.0L wouldn't run unless the pressure was between 80-100psi. maybe that was the case......they didn't need it to run but they can't clean out. when I had the 4.0L in my truck it had 80lbs min. at the fuel rail all the time. the filter is a good idea but I don't think it would have 55lb with a 60lb pump if it was clogged.