Low friction rings
 

I believe that our low friction piston rings require engine vacuum to seal and perform properly, would be then safe to say, that if you have a vacuum leak your engine would not be producing 100% of it's power?

after replacing a leaking (cracked AOS, accordion hose), now the engine does it seems to run smother and more powerful, does this makes sense..?

My 3.4 engine has a bit over 80k..

They are low tension rings against a low friction cylinder wall, but yes vacuum leak could cause slight loss of ring seal. Leaner air/fuel ratio from eliminating "false air" getting into intake without flowing thru the mass air sensor, is probably biggest reason for the improvement.

+1 What ^^^^ said.

Yes, it makes sense..!

My car must be running better now because it has the correct mixture.

I was getting about 20mpg, I will see after the next tank if something changes with the mpg, thanks again!
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