Having a Misfire issue after PI intake swap on 96 Mustang V8

So, I did the intake manifold swap for my car. Went from a crappy Dorman intake for a non PI motor and put on the Ford Racing Performance Intake manifold. It was actually used and off of a 2002 Grand Marquis but same crap right.

I now have a misfire. Yesterday she ran like a top! Now testing again tonight I don’t know. Luckily here’s a video!!


View: https://youtu.be/4-Sugrlh0JI


Misfire is similar to when I was leaking water in the spark plug holes with the old intake but know that isn’t happening.

So far, No leaks anywhere

I did put do-electric grease into each spark boot and squished it in there. Could that cause an issue? Also does the video seem like an injector issue. I re-gaskets all the injectors before installing.

please help fellow mustang clan!

Please watch video on youtube link!

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So, today
- i checked injector with stethoscope and they are sounding the same across board
-changed out coil packs with a Denso part and that did nothing
-checked each plug and they all look the same. I wiped off some of the dielectric grease i threw a lot of on the boots and that did nothing.

It feels like my car still has good power. I’m feeling like maybe i got a piece of dirt i. the fuel rail or something and it went into one of the injectors. I don’t know.

I am considering finding a noid light now. Also everything is grounded properly on the car

All I did is put a Ford PI intake into a non PI 4.6 SOHC engine
 
Thankfully so threw a code! Never ever been happy to throw a code before!!

P0136
P0135
P1131

So Bank 1 O2 sensors 1&2 are running lean.
The P1131 code i’m guessing the passenger side of the motor is the side where I am having injector and fuel type issues?

I know no one is answering but what do you guys think!

I can drive the car but can’t floor it or go up hills without it hesitating a lot yet