Mobil 1 5w30 - 7691 miles - 2001 Nissan Pathfinder

[nheitz]

Ok, I'm frustrated. I have a 2001 Nissan Pathfinder with just over 100,000 miles. This is Nissan's 3.5L VQ series V6. I've been getting high silicon & lead readings and figure out what's going on. The air filter seems to have a good seal & it looks clear just downstream of the filter. I don't see any obvious cracks on the intake. I did not have good luck with Amsoil Synthetic 5w30 running it for 1 year with their air filter & oil filter. I did it for 1 year & did not get good results... way out of viscosity, no TBN, & high wear metals. I decided to try it again for a year & had similar results. Here is that UOA.

I then ran Amsoil Synthetic 5w30 for 6 months & here is that UOA.

Then I switched to Mobil 1 5w30 & filter & replaced the Amsoil Ea air filter with a new Nissan OEM air filter to see if that was where my silicon was coming from. I ran this for 6 months & here is the latest UOA.

Please help!!! What do you guys think?

 

[nheitz]

I can't get the photo links to work!!!

 

[Drew99GT]

Ok, I'm frustrated. I have a 2001 Nissan Pathfinder with just over 100,000 miles. This is Nissan's 3.5L VQ series V6. I've been getting high silicon & lead readings and figure out what's going on. The air filter seems to have a good seal & it looks clear just downstream of the filter. I don't see any obvious cracks on the intake. I did not have good luck with Amsoil Synthetic 5w30 running it for 1 year with their air filter & oil filter. I did it for 1 year & did not get good results... way out of viscosity, no TBN, & high wear metals. I decided to try it again for a year & had similar results. Here is that UOA.

I then ran Amsoil Synthetic 5w30 for 6 months & here is that UOA.

Then I switched to Mobil 1 5w30 & filter & replaced the Amsoil Ea air filter with a new Nissan OEM air filter to see if that was where my silicon was coming from. I ran this for 6 months & here is the latest UOA.

Please help!!! What do you guys think?

 

[Drew99GT]

You can get dirt intrusion at other spots such as the PCV system. Might want to look at the grommets and vacuum lines that make up the PCV system. Look at all vacuum lines that either hook into the plastic intake duct or the intake manifold.

 

[nheitz]

Haven't done that. Ok thanks. But if there was a vacuum leak wouldn't it throw a trouble code? Especially since a loose gas cap can?

 

[Scott P]

Try uploading the photos to photobucket or another similar photo sharing service.

 

[nheitz]

For some reason they're working when I leave the posting & then hit back.

 

[buster]

Can you just type out the numbers? It's not working.

 

[nheitz]

Ok, lets try this again. I used Photobucket this time...

Ok, I'm frustrated. I have a 2001 Nissan Pathfinder with just over 100,000 miles. This is Nissan's 3.5L VQ series V6. I've been getting high silicon & lead readings and figure out what's going on. The air filter seems to have a good seal & it looks clear just downstream of the filter. I don't see any obvious cracks on the intake. I did not have good luck with Amsoil Synthetic 5w30 running it for 1 year with their air filter & oil filter. I did it for 1 year & did not get good results... way out of viscosity, no TBN, & high wear metals. I decided to try it again for a year & had similar results. Here is that UOA.

I then ran Amsoil Synthetic 5w30 for 6 months & here is that UOA.

Then I switched to Mobil 1 5w30 & filter & replaced the Amsoil Ea air filter with a new Nissan OEM air filter to see if that was where my silicon was coming from. I ran this for 6 months & here is the latest UOA.

Please help!!! What do you guys think?

 

[JAG]

The TBN is dropping much faster than I'd expect and the silicon is obviously high in all 3 UOAs despite an air filter change and no dirt in hose downstream of the filter. So one theory is that there is a hole or crack in a PCV hose which is letting unfiltered air into the crankcase and also not doing it's job of evacuating the blowby vapors (TBN killer). Basically, check every single hose, pipe, etc you can for holes or cracks. Even check areas that are low on the engine and possibly hard to reach.

 

[nheitz]

Thanks for the replies. Makes sense. I'll have to do a more detailed search for cracks. Does anyone know of another way to test for PCV leak other than finding the crack itself?