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hooked jump box up backwards on battery


Does anybody have any idea what this could be. Im not to familiar with these trucks or motors.
 
If there is no Check Engine Lamp/Malfunction Indicator Lamp, I can only think of one thing that can be causing this thing to not fire off, and that would be voltage sag. So let's go back through this. What kind of battery are you using? What brand/Where did you buy it from/How old? In all probability, that SOB was fried to mother knows where inside of it, and it sags down when cranking. Two: Go look again at all the wires. Make sure none of them got hot and melted. You might wish to give that battery a good charge, and jump it once charged from a known good vehicle (Keeping your relatives far away). I wish you the best of luck.
 
I replaced the battery and where is the fuel cutoff switch?
 
Fuel cutoff is in the passenger foot well, probably behind the kick panel on the outboard side.
 
The fuel pump comes on and primes as it should and injectors have power. What could hooking up a jump box possible fry
 
Is this a 4.0 SOHC or OHV? Seems to be a lot of discussion about alternator problems... kind of irrelevant until the engine is actually running, and we obviously don't have that. Also, if the fuel pump runs, the inertia switch is not your problem.

An engine needs 4 things to start: spark, fuel, compression, and reasonably close timing of all 4. No way did hooking up a jump box cause an internal mechanical failure, so we can pretty safely eliminate compression.

You are sure the fuel pump is running, but it doesn't sound like you've verified whether or not the injectors are pulsing. They need power to them, which you've verified, and they also need to be grounded by the PCM momentarily to actually shoot fuel. The correct test is with a noid light plugged in at the injector connector. It is POSSIBLE, and I stress POSSIBLE, to check for injector pulse with a test light by connecting the clamp to power and probing the PCM-controlled wire at the injector. However, this is not really a 'safe' test to perform as the drivers inside the PCM are not designed to handle the load of a lightbulb and it's possible that you could compound your problems. I remember reading that you sprayed carb cleaner or something at it and didn't get any kind of fire, so I don't think this is where your problem is.

You have pulled one spark plug and verified spark, however, it is possible for these coils to 'partially' die. You can use the easiest wire and plug to check each coil posts output. I suspect this is likely the problem, because of the carb cleaner test you performed. Also, it's not a bad idea to use a true spark tester or an old spark plug with a much wider gap when you are checking spark. It takes quite a bit more coil energy to jump a gap with compression and a fuel charge than to just jump in open air.

What does the 'Theft' light do? I don't remember what a PATS fault disables offhand, but most makes disable fuel when it enters anti-theft to prevent flooding. Does the check engine light come on with just the key on? Also, some of the fuses for the powertrain (ignition hot circuits, mostly) are actually in the interior panel, so make sure you check those as well.
 
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The PATS light blinks steady when the truck is sitting. When you put a key in and try to start if the PATS light is blinking really fast PATS is not allowing the motor to run. I don't remember if PATS will keep the starter from working. Maybe somebody can verify what PATS does.
 
What you said is correct. The starter circuit is hard-wired through the ignition switch and the PATS cannot disable it. However, if it goes into theft mode, the PCM will disable injector pulse to prevent it from running.
 
The PATS light blinks steady when the truck is sitting. When you put a key in and try to start if the PATS light is blinking really fast PATS is not allowing the motor to run. I don't remember if PATS will keep the starter from working. Maybe somebody can verify what PATS does.

Depends on the year and model. The first few years of PATS would kill the fuel injectors only. Then it phased over to a starter disable. Some years and models kill both the starter and the injectors.
 
Its a 4.0 soch. I checked power at everything again and everything had about 12.7 volts. I took the fuel line off at the fuel rail and there was no fuel pumping at all. Then i checked each coil for spark and they all had spark. Then i checked to see what the voltage draw was while cranking it droped down to about 10.9 11.1. I still here the fuel pump come on and i dont have any fuses blown. The pats system works correctly it comes on and Blinks three times then shuts off. I have the day off so id really like to figure this out.
 
Its a 4.0 soch. I checked power at everything again and everything had about 12.7 volts. I took the fuel line off at the fuel rail and there was no fuel pumping at all. Then i checked each coil for spark and they all had spark. Then i checked to see what the voltage draw was while cranking it droped down to about 10.9 11.1. I still here the fuel pump come on and i dont have any fuses blown. The pats system works correctly it comes on and Blinks three times then shuts off. I have the day off so id really like to figure this out.

Sorry, I was thinking your truck was older when I posted about the starter circuit being hard-wired. I pulled a wiring diagram for an '01 SOHC to be sure - the PCM grounds the starter relay, so if it's cranking, you should be ok there. If you removed the pressure line and keyed it up and got no fuel out, it sounds like you're onto something. If you have a pressure test fitting on the rail (on a Ford, it looks like a tire valve stem up on the fuel rail), consider getting a fuel pressure gauge and doing a proper pressure test. It's the only way to be certain.
 
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The sparkplugs were dry too so i know for sure im not getting any fuel. Im gonna work on it a little later today and check fuel filter and take the line off before fuel filter and even see if its pumping out of the tank.
 
I would put money on it that you fried the ECM when that happened. There is a reason why they say DO NOT hook the cables up backwards. A hefty, expensive mistake. Go pull an ECM of the same make, model and year and hook it up. I would almost guarantee that it will start then.
 
The fuel pump was not pumping any fuel so i went and bought a new one. I listened for this one to prim and it did. I removed the fuel line after the filter to make sure the fuel was pumping through the filter and it was. I then removed the conection to the fuel rail and i had fuel pumping to the injectors for sure. So now i know i have fuel for sure. And i already know i have spark. I figured after putting the new fuel pump in it would start right up but it didnt do anything not even a cough.
 

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