'94 F150 5.0, 4R70W, 4X4, EBay problem child

When I bought the truck, it had the wrong 5.0 in it, ran on 7 cyls.,and not well @ that. Ebays resolution dept. and CarFax both fell down badly on this one.

I built another engine (306" roller cam) for it and it STILL SEEMED TO HAVE NO POWER.

EEC IV codes 53&63 - TPS voltage both too high AND too low. 2 new sensors - no change, re-pop EEC = kick/no start. Original (?) EEC back in = run fine for 50 mi., then lean misfire steady state (50 mph), no power. Like a banshee WOT.

Now codes 53/63, 172/173 (HEGO rich AND lean. AND these codes were set w/ the TPS sig. ret @ .91vdc @ idle.

Battery disconnect to clear codes, but as soon as it went closed loop after restart, the codes set again. I’m stumped, frustrated, and today, it blew a brake line.

A fresh idea (or a match) would be nice,

As an added bit of info, the dealer says that per calibration on the pillar, the EEC in the truck is correct (F4-12A650-APA). The engine in the truck was a pre-'92 flat tappet, obviously not original, and I THINK (but don’t know for sure) that all of the codes mentioned above were probably present when I bought the truck.

You’re not trying to run a mass-air ECU on a speed density motor or vice versa are you?

I’ll second FoDaddy on this. Mixing and matching mass-air and speed density systems will open up a real can of worms. I got tied up in one of these about 5 years ago.

You’ve learned that eBay’s “protection plans” are totally worthless and CarFax is half-worthless since CF does not track engine swaps, etc. unless it was reported by someone. EBay has become a dumping ground for a lot of problems and the only way I would buy a vehicle from eBay would be if it were reasonably close and I went and took a look at it first.

The engine in the truck when I got it was a flat tappet 5.0. All the info I have said that '92 UP 5.0s were ALL roller cam. That’s why I built the currrent engine as I did. The EEC that’s in it is listed @ Ford Fuel Injection as being for an E/F series 5.0 w/ a 4R70W (AODE) trans which also puts it '92 up.
The truck IS a MAF app.
It runs better now than it did w/ the old engine, but the contradictory codes while the sensor voltages are good are what have me addled, and keep me thinking that the EEC is the root cause here.

Believe me, I know the differences between EECs. My '90 MK VII project (347", MAF,T5, originally SD, 22 lbs. lighter after re-wiring - THAT WAS A PROJECT! - uses the original SD EEC for cruise and a MAF A9L for engine management)
This is hardly my 1st time @ the rodeo, I’ve just never run into anything like this before.

I think your info is incorrect and lifter type varies by application, although I don’t think lifter type has anything to do with your problem. However, the camshaft profile could be.
My Tinker Toy car here has an 87 Mustang GT 5.0 engine in it and it has a factory roller cam/lifters in it.