I just posted this on the Bronco forum but thought I'd post it to the F150 page as well. My '87 302will not fire. My timing is correct and the only Key on Engine off code is an out-of-spec TPS reading. The reading is 1/2 volt lower than it should be with a closed throttle. As I open it up, the reading goes to 4 volts. It isn't a WOT condition. I don't think this is my primary problem. I don't have a puff of smoke or a pop to indicate that it's getting fire and gas in any cylinder at the same time. The timing is correct and the plug wires are correct. The ignition module tested ok and I see spark if I lay the plugs against the frame. I know this isn't a perfect test, but keep reading...

The engine will turn over a few times rather slowly, but not so slowly that it shouldn't crank...then it'll hang. If I let it sit a few minutes, it will turn over a few more times....and it'll hang again.

I took the serpentine belt off thinking an accessory was locked up and it made no difference. I didn't hear any noise that would make me think I'd broken a cam or timing chain. I removed the spark plugs to see if I could find a particular cylinder causing the problem. The hanging continued as I removed plugs 1-7. These plugs were completely dry. When I removed plug 8, the engine spun freely, but it spewed gas out of the #8 cylinder. I think the "hanging" I've seen is occurring on the compression stroke on the 8th piston. It's trying to compress several ounces of liquid gas. Is it possible that an injector has failed so that it offers no resistance to fuel flow? Can it be effectively blown open so that it gets all the gas while the others are starved? The engine can't run because the only cylinder with gas is completely flooded.

My next step is to drain the oil/gas mixture, fill it with new oil, and remove/inspect/replace the fuel injector from the #8 cylinder. Unless...one of you has a better idea. Does this make any sense? Can you think of another failure that could cause these symptoms?
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Sounds like a good move to do, let us know how it turns out and what the injector looks like.

 

Yes.. sounds like you have a stuck injector. Remove them and have them cleaned, or replace them.

 

If the injector was offering no resistance to fuel flow, you would have no pressure with key off. Did you test the pressure to see if there is a loss?

 

Try spraying some gas into the air tubs with a spray bottle and see if it will start and then die. If so then your not getting enough fuel to run the truck. Injectors arent real expensive. Summit has the best deal I found.

 

Check the fuel pressure regulator also. I saw one go bad on a 351W that filled #8 with gas exactly as you describe. Pull the vacuum line off and cycle the key to run the fuel pump. If fuel shoots out the vacuum nipple, the regulator is bad. This is a much more common failure than injectors.

 

Brown 4x4 called it perfectly. Gas spewed out of the vacuum connection on the Fuel pressure regulator. I replaced it and drained almost 3 gallons of gas out of the crankcase and am back on the road. I let the first round of cheap oil warm to operating temperature and circulate a while and changed it again. I wish I'd realized what was happening sooner, but it doesn't seem to have caused any other problems. Thanks to all who replied to my post.