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blue62 · 08-26-2021, 11:07 AM

I hate to say it but I think you still have valve train issues on bank 2.
A leak down test only tells you if the valves and rings seal (or not) when the piston is at TDC. It is a static test.
It can't tell you if you have weak valve springs or lifter issues, or worn cam lobes, or...

You could do a vacuum test. It is an operational test. It will tell you how well the cylinders are filling with fuel/air mixture. Which is affected by any type of valve train issue. If a cylinder or cylinders are not filling with fuel/air properly it causes performance issues.
If the test is done correctly (and that is very important). It should give you a very good idea as to if the valve train on bank 2 is an issue or not.

Another (possibly) important thing to know is:
What RPM range are the misfires happening in????
Does it misfire in just a certain range like idle? or mid range? or high RPM?
Or are the misfires all across the RPM range??

Why did the head need replaced in the first place???
Did you ever have a misfire issue on bank 2 before replacing the head???

Edit:
Just re-read your posts.
What do you mean in post #3 when you say you "swapped" valves????

08-26-2021, 11:07 AM	#5
blue62 Registered User Join Date: Aug 2018 Location: Woodland Wa Posts: 1,309	I hate to say it but I think you still have valve train issues on bank 2. A leak down test only tells you if the valves and rings seal (or not) when the piston is at TDC. It is a static test. It can't tell you if you have weak valve springs or lifter issues, or worn cam lobes, or... You could do a vacuum test. It is an operational test. It will tell you how well the cylinders are filling with fuel/air mixture. Which is affected by any type of valve train issue. If a cylinder or cylinders are not filling with fuel/air properly it causes performance issues. If the test is done correctly (and that is very important). It should give you a very good idea as to if the valve train on bank 2 is an issue or not. Another (possibly) important thing to know is: What RPM range are the misfires happening in???? Does it misfire in just a certain range like idle? or mid range? or high RPM? Or are the misfires all across the RPM range?? Why did the head need replaced in the first place??? Did you ever have a misfire issue on bank 2 before replacing the head??? Edit: Just re-read your posts. What do you mean in post #3 when you say you "swapped" valves???? Last edited by blue62; 08-26-2021 at 04:13 PM.