1990 F-150 4.9 Please Help!
 

Well I'll start with a little background, new plugs & wires, rebuilt distributor, new IAC, New battery, New Map Sensor, New Fuel Pump and Filter, New Ignition switch, swapped 4 speed transmission for a C6, fully loaded, front tank removed, no catalytic converter, just 2 1/4 with a glasspack. My Problem: after driving about 15 to 20 min it has no power, you give it gas it just pops and bangs and loses speed, use a little gas and it is fine, let it sit over night and it is fine till you drive it for awhile. Also when it is acting up the O/D button flashes which I find weird cause of the transmission swap it does not have over drive, any help would be greatly appreciated!

Pull codes,test map,egr,tps and clear codes.

unable to pull codes, but after some reading on here I decided to check my timing, I had to set my gun 90 degrees back to find the mark so I set it to 85 degrees and took it for a drive and all seems well, now why in the world is my mark of 90? i'm assuming i'm 5 degrees BTDC now but unsure cause the whole 90 degrees off thing.....

I think it should be 10. Does it die if you bring it lower. Sounds like the dis is way off.

This is how to pull codes:

https://www.f150forum.com/f10/how-re...es-obdi-10907/

You're probably looking at the wrong timing marks. The ones you want to use are on the passenger side, not the ones on the cover on the driver side.

Does it pop and bang through the intake or exhaust? Backfiring through the intake manifold is known as a lean misfire, exhaust backfiring and black smoke is a rich misfire. One way to take the computer "out of the loop" is to disconnect the spout connector near the distributor and see if it still happens. If it does still happen, you'll know the problem most likely lies in the fuel/ignition system. If it doesn't happen, you'll know the problem is computer controlled, sensor or output.

Guess im dumber than a monkey
 

still can't get codes, ran good for about 150 miles and back to what it was doing, going to try to set the timing to the other mark, yes it spits and sputters thru the intake, i'm new to fords so please no more making fun of me, im here for help not to be put down! i will set to 10BTDC, also exhaust came unhooked when it started acting up this time, I know when I was racing Chevy's yes chevys it made alot of difference from open manifolds to vs some sort of exhaust

one problem to another
 

I got it to idle for long enough to set it 10BTDC, but it is idling up and down 2 to 3 time till it dies now going to look thru forums for help any other ideas would be appreciated

Clogged converter? :unsure: