Having some issues I cant figure out

[94_PurpsRange]

Good morning everyone! I would like to start by apologizing for not being around more. my wife had some major surgeries last year and this year and it's been a bit wild, and I have had to put off some work on my trucks.

Anyways, I have a 94 XLT 4.0L and I am having an issue I can't seem to pinpoint... So, the truck drives fine... except when I give it more than 1/3 of the gas... once I try to accelerate to get up to speed or even simply getting on the freeway it falls on its face every time... I put the gas down and it attempts to down shift and go but i almost immediately lose all power no matter how far i put the pedal down. BUT if i let off the pedal and give it gas again it will go as long as I don't give it more than 2/3 of the pedal. it gets up to speed and drives normal if I don't give it too much gas.

Here are the things I have done to try and fix this issue...
Fuel filter
Fuel pump
TPS sensor
Air filter
MAF

I am kinda at a loss for words on it... Now my brother (who own a shop) says "there is a chance it's still one of those things BUT I got a defective Chinese piece of shit part"... the issue is I am not sure which of those it could be... So, I am looking to see if anyone has ever been thru this kinda shit and if anyone has some advice to what I could be missing all together?

 

[SenorNoob]

Can you check codes?

Testing EEC-IV Equipped Engines
OBD-I Diagnostic Trouble Code – Ford 3-Digit Codes

 

[94_PurpsRange]

Can you check codes?

Testing EEC-IV Equipped Engines
OBD-I Diagnostic Trouble Code – Ford 3-Digit Codes

I personally do not have the ability to check the codes. My brother on the other hand does... it doesn't always throw a check engine light and when we ran the scan tool on it last night there were no codes or stored codes...

 

[Curious Hound]

1. Make sure there are no leaks to get into the intake, especially between the MAF and the throttle body. If air bypasses the MAF, you will have trouble.

2. Can you check fuel pressure? Many times auto parts stores will rent or loan a fuel pressure testing tool. That can help you figure out a fuel pump/filter issue.

 

[94_PurpsRange]

1. Make sure there are no leaks to get into the intake, especially between the MAF and the throttle body. If air bypasses the MAF, you will have trouble.

2. Can you check fuel pressure? Many times, auto parts stores will rent or loan a fuel pressure testing tool. That can help you figure out a fuel pump/filter issue.

hmmm... i didnt consider the intake.. I do believe that my intake box might be cracked a little bit.. and i had to makeshift something a few years ago to go around the intake hose to secure it to the throttle body. I will definitely look into that as well.

Yes i can check fuel pressure, i will do that this evening after work.