Hello guys, truck in question is a friends 96 F150, its 2wd, e4od, with a 5.0, approx 175,000 miles. He's been fighting vacuum leaks for a couple months now, upper and lower intake manifolds were pulled for gasket replacement, distributor was pulled too and that's were our problem lies now...

The engine is back together, I dropped the dizzy back in and lined it up with the mark(s) that the hold down clamp had left on it, figured that should have got her pretty darn close to being timed right as the distributor hadn't been moved or disrupted in the 17 years prior. Started the truck up and she seems to idle alright but under load it burps and pops out the intake. Sooo shes too far advanced... I went back to square one, found tdc on cylinder 1 on compression stroke, rotor is pointed at #1 under the distributor cap. Took a wire brush to the harmonic balancer, marked 10btdc with a yellow paint pen, I marked the timing pointed in red. Dug out my timing light and fired the truck up and I cant see yellow anywhere on the balancer. I shut the truck off, I located the ignition module up by the master cylinder and pulled the little jumper out, tried to start the truck and it did not fire, i turned the distributor about a millimeter to retard it a little and tried fire the truck again, still no go... I repeated my procedure of retarding the dizzy a hair and attempting to start the truck atleast 20 times, the truck never did fire back up. Out of frustration I stuck the jumper back in and the truck fired up, it idled fine, and still popped out the intake under load. It acted exactly the same as it did before dispite the distributor being turned approx 1/8-1/4 inch in the retard direction, I checked the timing light again and still no sign of my yellow mark.

I have an Obd2 scanner that I can read live data on, I plugged it in and fired the truck up, at idle with the jumper in place I can watch the screen and see the spark advance bouncing between 19-22, which seems waaaaaay too high for a stockish 302.

Now I'm not entirely new to timing fuel injected 302s, I built the 306 in my '96 F150 which I timed just fine at 13btdc (with supporting mods) I've also done the "six liter" tuneup on the stock junkyard 302 in my 94 f150. My understanding is that the jumper needs to pulled to set base timing, correct? Yet no matter what I do with this particular truck I can not get the thing to fire with the jumper unplugged, and no matter how many times the dizzy is adjusted and the tuck is fired up (with jumper in place) my scan tool is consistently showing 19-22 degrees advance at idle.

Basically I'm finding myself completely dumbfounded, been screwing around with this truck for like 4 days now and cant figure it out. Is there something I'm missing?? Other then a stumbling idle due to a vacuum leak at a bad manifold gasket the truck ran fine before. We've solved that issue, truck seems to idle fine and pulls decent vacuum according to my vacuum gauge, now it just runs like crap at anything over idle

 

So start the motor with the spout plug installed and remove it once it has settled down to a steady idle, this is the way I always do it.

Popping out the intake suggests you have crossfiring between plug wires or misrouted wires, this motor should use the HO firing order.

19-22deg advance at idle sounds about right to me as well.

 

Well now we have three opinions, but I think 19-22 degrees seems awfully low for idle with the vacuum advance. It ought to be around 10-12 without the vacuum advance (with the SPOUT removed). I'd expect closer to 30 degrees with the SPOUT back in.

If I'm right (which has happened once or twice, but not so often that I always count on it) then it would seem the timing is retarded. Try advancing the timing about 10 degrees and see if you can get it to fire with the SPOUT removed.