VY SS RUNNING ON 4 CYLINDERS

[sswagon]

Hey guys, I've recently ran into some issues, and needing someones expertise as im stumped. Car is completely stock aswell







I have a vy ss thats running on 4 cylinder, cylinders #2 #4 #6 #8 are not firing at all nor is there injector pulse on that side. Problem is persistent, but for one day it ran absolutely fine the next started misfiring and hasnt stopped since



Things ive done

-replaced igntion leads and spark plugs

-replaced 02 sensors no luck

-swapped injectors from bank 2 (non firing side) to bank 1 and problem stayed at bank 2

-Swapped coils to otherside and problem stayed at bank 2

- Checked ground they seem good



Im starting to think it could be a bad pcm or potentially something going wrong in the harness as its stays on bank 2 always. Maybe even a sensor issue somewhere like cam sensor?



Has anyone seen a problem like this before, ive spent countless hours reading other threads.

Others have had issues like, blocked cats, bad harness, bad pcm or the dreaded bad timing stuff like that but i dont know where to start.



Please if someone can help me it would be much appreciated. if theres anything ive missed I'm more than happy to answer.

 

[Immortality]

Sounds like a wiring issue or PCM problem.

Is there power (12volts) on the injectors on the problem bank?

 

[sswagon]

I took it to an auto elec this morning and he said there was power to the coils and injectors

 

[Immortality]

This might help. This drawing is for a VT LS1 but fairly sure the VY is the same. Both the coil and injectors are switched directly from the PCM. If there is power at the injectors and coils than it suggests an issue with the PCM side. I don't think there is any sensor (other than exhaust O2 sensors) that are tied to only one bank that could cause a no fire issue.