The lab recently flagged my UOA for critical fuel dilution. It was at 5%, viscosity only slightly out of grade for 5W-30, TBN was above 2, below average amount of wear metals after 4k OCI. They added their."canned" response,
"Check for source of FUEL LEAK. Fuel is at a SEVERE LEVEL. Fuel dilution may be caused by component faults related to injectors, ignition/timing, or excessive blow-by. Additional causes include heavy throttle application, engine lugging, frequent short trips and excessive idling. FUEL DILUTION reduces the viscosity of the lubricant which decreases FILM STRENGTH and LUBRICITY and may lead to increased wear."
I have had previous lengthy discussions with them about whether this is actually Critical Fuel Dilution, but they maintain their stance, despite their own TSB stating that upwards of 7% is typical for a GDI engine. I had already spent fair amount of money replacing components. I finally told them to go read their own bulletin and re-consider the results of the UOA.
"Flagged data does not indicate an immediate need for maintenance action. Continue to observe the trend and monitor equipment and fluid conditions....FUEL DILUTION reduces the viscosity of the lubricant which decreases FILM STRENGTH and LUBRICITY and may lead to increased wear."
What is frustrating is the analyst have only 60 seconds for each report and have to resort to using canned responses, and it is a different person each time. I had a decrease of Boron by 75%, but no comment, and when I asked, they said they cannot identify each additive variation, and was unable to comment or provide any information about the loss of Boron. The New Fluid Reference was right there on the report, but they could not comment on it.
Has anyone else had similar experiences?