Hey, Got a 1994 F-150 with a 351. LOTS of work done on this thing. Here's the situation;

Blown tranny, removed and installed new one
While it was out, did oilpan
To DO oilpan, had to remove upper intake
Ported it while it was off, Cleaned Throttle body ( I think this may be problem)
Broke EGR diaphram, bought a used one
Broke EGR downtube, Brazed back together
Fixed vacuum lines
New plugs, wires, cap, rotor, fuel/air filter
Did not touch distributor
Truck WAS running before this work was done
Now, I cleaned INSIDE the throttle body. I read the sticker AFTER...

The truck will not start, Just cranks and cranks. With Ether, it backfired through the throttle body. Timing's out, right? Checked plug wires, They are ok. Took off, re installed, double checked diagram. (I have Mitchell's) Still wouldnt start. Pulled #1 Plug, lined up exactly where I had #1 wire set up at. What the HELL Did I do???

Please help, this has been a two year project, I need to get this thing running!

 

First thing to realize is that when you crank and no start the fuel in still being injected into the cylinders and can flood the plugs so you can get into a double whammey on a no start.
Check for spark at crankover, if good put a fresh set of plugs in and test fuel pressure with a gauge before cranking by repeatedly turning the key to run a few times but not try to start the engine.
Make sure the ECT, ACT and TPS are all plugged up solid.

 

Hey, truck has fresh plugs, and everyhting is plugged in tight. Have good solid spark, But the plugs were wet for a bit, your right. I'm at a complete loss here. Still backfiring through the Throttle body. Could this be because I removed the film off the inside of the throttle body?

 

No. That will cause problems down the road, after several months of driving. It won't affect it now.

Which firing order are you using? You know that 1-4 are on the passenger side, right? No disrespect intended, but I've gotta ask.

Next time, hold the gas pedal to the floor when you try and start it. This will shut off the injectors until it fires.

 

Hey, no disrespect taken. Yeah, I know that the banks go down the side, 1234, 5678. I checked for injector pulse, theres pulse. Theres fuel, and theres spark too. Pulled the plugs, they are soaked. I am going to disable fuel and spark, and blow out the cylinders with a dry crank, then install brand new plugs.I will be back in about an hour and a half to let you guys know whats going on. Thanks!

 

Hey, Got a bit closer I think. Checked for spark again, and this is what I found;

When cranking, the spark isn't a steady fire, it will fire, then pause for two or three seconds, then fire, then pause, etc. Also, it's an Orange spark, not blue like it's supposed to be. Faulty ground? Bad coil? AGHHHHH!! HELP!

 

I'm not sure about your spark problem, but if the plugs are wet, and the motor turns over without trying to start then you're probably flooded. Try what pkrwud said about stomping the gas and cranking it.

If you think you're getting a weak spark, grab the spark plug and have somebody turn the motor over a few revolutions.

 

Hahha, yeah that'd be fun. Anyways, I changed the plugs, checked for injector pulse, and found there to be fuel. I blew out the cylinders with a dry crank too. The spark is weak, and doesn't pulse rapidly, it skips every few seconds. This HAS to be the problem, but why? Where is the ground for the coil? What could be causing this? I'm stuck....

 

Installed a new coil, Still nothing. I checked for spark, I had good spark. Checked for spark about 10 minutes later, NO SPARK! WHAT CONNECTOR DID I LEAVE LOOSE? Please guys, I'm really in a fix here, help!

 

Get a 12v test light, and ground the aligator clip, and touch the positive side of the coil with the key ON. It should light up brightly. If it doesn't, you have a problem with the signal from the ignition switch to the coil.

If it lights up brightly, move the test light tip from the positive side of the coil to the negative side of the coil, and have someone crank over the engine. It should flash. If it doesn't, there is either an opening in the wire from the negative coil post to the ignition module, or the module is bad.

Post your results.

 

Well PKRWUD, both sides had power, and both kind of flashed. They don't really flash, they just dim when It's being cranked. That sucker is getting harder and harder to crank over, almost like something is seized. (Full battery too) I'm getting sick of this truck, I really am. I've had no wheels for over a year now, and It's ridiculous. If I put the fuel filter on backwards, would that hinder it's ability to start? The plugs are getting fuel, I know that. Dammit!

 

Okay, here's what you need to do. Unplug the harness connector at the coil and at the ignition module. With your multimeter set to ohms, measure the resistance between the negative coil wire to the second wire from the bottom at the module connector. It should be less than 5 ohms. If it's more, the problem is in that wire, and it must be fixed or replaced.

If it's 5 ohms or less, next check the resistance between the negative coil wire and ground. It should be greater than 10,000 ohms. If it's less, that wire is shorted to ground, and must be fixed.

If everything is as it should be, replace the ignition module.

 

im not sure what years ford used the duraspark module (mounted to the firewall a black box ) but i remember them having a problem with no start, it had to do with a resistor or something going bad , alot of people cut it out and soldered the wires together and it ran fine with no problem. let me check on alldata at school to see if yours had it.

 

Hey...Im at a TOTAL loss. I checked for spark again, It had spark. I changed the igniton wires back to where I thought they should go (MITHCELLS WAS WRONG) and It started right up. Cant even believe this! Everyone that was here helping me out, you guys kick ***, I'll be sure to repay the favor with my knowledge. Thanks guys!