I have a 1999 Ford f150 v6 with some work done to the motor, has a morana stroker kit. missing cats, needed slave cylinder, missing fuse number 20 in distribution box* (this alone caused about 8 codes). it had previously been setup with a pro-charger which was removed and 42 # injectors. Previous owner said trucks running lean though he thinks computer compensates with rich fuel mixture and that fouled the plugs so I bought it not running. clean the upper intake, replace the injectors with stock size, clean spark plugs re-gap and install. after this the truck runs ok for about a week or maybe around 250 miles. keep getting lean codes p0174 and p0171 iirc and eventually hard to start so I dig in and get to the lower intake and clear evidence its leaking air and some coolant. unfortunately snapped a ton of bolts into the head, so heads come off too. take care of this and reassemble, go to start and crank no start. mileage is all dashes and pats is active. runs with ether in the intake so no issue with the assembly mechanically. go to hook up a tuner to it and its getting a code that it cant communicate but pats wouldn't lockout the tuner like that. thinking initially about the fuel pump bc i didn't notice the dashes and pats at first, I start in the power distribution box, check all the fuses, jump the fuel pump relay with return gas line open so I can cycle gas and make sure pump runs fine. good to go. then i notice dashes and see the pats. after this i start testing electrical items and happen to pull fuse 10 (fuel pump circuit again just to check) at which point pats figures itself out. mileage is numbers and the tuner can connect. i jiggle power distribution block and reinstall the fuse and it sticks. ECM is active no problem. tuner asks to cycle key for something and this resets pats. the workaround doesn't work again after this. it goes from all dashes on mileage to blank mileage. battery cable off resets it to dashes. took apart ecm and its perfect really. took apart power distribution block and its fine. reseated a ton of ground wires, getting good power/ground to the ecm on the proper pins. i'm hoping this info can help someone get me in the right direction. i also noticed evidence that some of these electrical tests im doing have been run before. aftermarket dash or the guy colored it. had a viper alarm system in but i havent used. id be interested to hear any thoughts. Pats code is 16, i switched out the transponder in the ignition but that didnt do anything.

 

I don't find the problem interesting at all . You bought somebody else's effed up mess they couldn't fix.... And you having trouble with it too. No surprises there.😏. That's usually the way it goes. When you start talking about non-stock modifications.... And ridiculous things like superchargers, tuners and 42 lb injectors .... There's no telling what the previous owner(s) did to it .

Do you know why the supercharger was taken off? Because the guy could sell it for some $$$ and the truck was nearly worthless in nonrunning condition. . He was trying to get the maximum money back out of his mess for himself.

 

Agreed, suckers are way too common to be interesting.

 

Thanks for 2 cents fellas. Anyway, the truck frame is perfect, cab is perfect, no rust, interiors in great shape, trans is fine, bed has no rust. Drilled and slotted rotors for 1000 dollars is worth it all day in my book. I know it changed hands a few times and people did different things depending on their circumstance. My circumstance is i want to figure it out. The engine ran fine even when lean and sounded great actually. As far as i can tell there's not much mods done to the wiring. Pulled dash test codes d147 d262 and -40 on cylinder temp. Mightve cracked wires to the temp sensor on the heads. No test for temp, scp doesn't read to power up pcm properly, then key can't be read for dtc 147.

 

Wow
Put it back to stock
Get rid of the 42 lb injectors
Who would try to hotrod a 4.2?
Bag of worms was the result
Maybe put a reman or good used stock 4.2 in the truck so it runs

 

Extremely lonely, very desperate pro-charger.

 

If you know what you're doing...... You can sometime make a silk purse out of somebody else's f up.

Back in the 1990s I had two co-workers.... One of which had always wanted a Camaro and finally bought one that was used for $12,000. . It developed some kind of problem and he ended up taking the engine all apart trying to fix the problem and couldn't. To make a long story short he gave up on it...and sold it to the other coworker.... In pieces. For $1500 . The other co-workers dad owned an auto shop and he had grown up working in it..... And he put it back together , got it working right, and had a nice car for nearly nothing. I kind of recall him telling me that the fix the car actually needed was something simple and that the other guy had just done dumb things taking engine apart.

 

Im dumb sometimes, love the thought that i did something stupid and can go back and fix it easily, like tossing a wire harness back together. Id be so happy

 

update: did a bunch of things but the thing that fixed it most likely was in the dash cluster. when I took it apart had a weird situation where a resistor on the circuit board had leads soldered too long and both ends were touching the plastic between the guage motors and the circuit board. maybe through some water vapor it had shorted out into the electromagnetic field around the motors to spin the odometer and other guages. it left some neat looking electrical stains on the plastic in the dash cluster. filed the ends of the resistor down, and soldered the pin for the mileage while i was in the cluster. i did find one other tiny short to ground on what appears to be the circuit that would light the check engine light on the circuit board. i cleaned it up a bit, just scraping some of the charring back. as of now it starts and i do not have the electrical fault that was causing the failure to communicate and stopping me from starting the truck. The truck starts and runs now.
unintended consequence is now the cel doesnt light up at all, might need to do a trace repair on that circuit or i might live with that light not being able to come on ever again. the guage motor that turns coolant temp guage isnt working either so i may go back in and replace that motor with the trace repair

 

It's ready for another Pro charger.