I added fuel additive in my gas and the injectors seemed to take a crap. I removed and tested each injector (bad) Went ahead and replaced all 4. Installed new ones and the truck still has a rough idle and low oil pressure at idle (20psi). Any ideas or tips are appreciated!

 

Tell us what you are working on first. I assume its not a 2002 2500 suburban with the 8.1 and 4L85E. But I could be wrong.

Most of us are scattered across the world so the more info you can give us the better we can help. Pictures of special areas or problems speak volumes as well.

 

20psi at idle is too much if 22re. assuming it is a 85 Toyota. Should be under 5psi at idle. don't know how you tested 4 bad injector and it was still running. I would assume you also checked fuel pressure? Check intake tube. Check compression, which would typically be between 150-180psi, with not too much change from cylinder to cylinder. Maybe water in distributor?