Random misfire at idle 454 vortec

[elevatorman]

So i have found a schematic finally for my truck my only confusion is the pinouts.
All pins are labeled a,b,c and d i have yet too figure out of the four colored harness connectors which they are

 

[elevatorman]

So i have found a schematic finally for my truck my only confusion is the pinouts.
All pins are labeled a,b,c and d i have yet too figure out of the four colored harness connectors which they are

Nevermind just traced them out.
A-Blue
B-Red
C-white
D-Black

 

[elevatorman]

Update going while ohming out the injector harness from the ecm everything is solid except i made too injector 8 and there no wire too b5.
And i could not find any on the b plug. So currently trying too probe all connectors too find it

 

[elevatorman]

Well definitely have zero signal wire too number 8 from ecm. And i cannot find it loose in the harness up by the relay box anywhere. I guess my next issue would where too get the pins too add the wire in.
Im still confused because i did a injector balance test and they all bled down equally unless number 8 somehow is getting a cross signal from where ever the wire is in the harness. But doesnt seem possible when doing the test only firing the one.
Also my miss always is dominant on cylinder 1 and bank 1 lt trims are higher.

 

[Schurkey]

If #8 isn't misfiring, and there's no problem indicated with #8 on the injector-balance test, you're maybe reading the schematic incorrectly.

Misfire results in a false-lean O2 sensor reading, which is maybe why the fuel trims are in rich-command for the bank that #1 is on.

 

[Schurkey]

So i have found a schematic finally for my truck

WHERE did you find this schematic?

 

[Carlaisle]

Your key on engine off fuel pressure is too low. You said you replaced the FPR. What was the part number on the one you installed? The parts stores give people the wrong one all the time. They physically fit, but the pressure is not correct.

Did you only find and replace a single leaking injector? i.e. do you currently have one new Bosch injector and 7 OEM injectors?

 

[elevatorman]

If #8 isn't misfiring, and there's no problem indicated with #8 on the injector-balance test, you're maybe reading the schematic incorrectly.

Misfire results in a false-lean O2 sensor reading, which is maybe why the fuel trims are in rich-command for the bank that #1 is on.

The schematic i had was wrong for injector 8 i did find it on the blue connector

 

[elevatorman]

I just performed a leak down cylinder 1 tdc and i believe the worst has been found. Cylinder 1 100 percent loss instantly too crankcase. Bad rings

 

[elevatorman]

Your key on engine off fuel pressure is too low. You said you replaced the FPR. What was the part number on the one you installed? The parts stores give people the wrong one all the time. They physically fit, but the pressure is not correct.

Did you only find and replace a single leaking injector? i.e. do you currently have one new Bosch injector and 7 OEM injectors?

All 8 new bosch