My last 2 UOA's have showed elevated lead but nothing else elevated. In fact the rest of the metals are below most averages. The only thing changed recently is a slightly more aggressive tune. There's no audible knocking/detonation and the engine purrs like a kitten still.

Anyone with more experience with FI UOA's care to place a guess on what's happening?

 

looking at the history on that sheet it looks like bearing material. im not sure which is in which layer but looking it had a high copper content that tapered down and as it tapered down lead shot up. levels dont look crazy high though looks like it might potentially be the "particle streak" that blackstone lists on there site. noticed moly was high and went down same for boron, moly could be additive or oil but i know boron, copper, and lead are all bearing materials. ill admit ive never had a oil analysis done though im just making educated guesses but thats what it looks like to me.

 

Welp the only thing that changed before the lead shot up is the tune. Do you think it could just be the extra power? It's about 15tq and 30hp more (with lots more area under the curve) and right on the edge...any more and I ping due to turbos running out of breath (AIT goes thru the roof). I wonder if I should revert to the old timing map just to see if that's really the case...but if the bearing material isn't 'excessive' is it really worth it? I just don't know what to worry about or not.

 

in my opinion i wouldnt worry, like i said it looks like it might have been just a "particle streak" that the list on there site as a small bit of dirt getting in there and spinning around shaving some off the bearing. obviously not very much looking at the numbers and i wouldnt worry at that still low level. what did blackstone say?

 

If it is the bearings, I don't think swapping the old map back will make a difference, what's done is done.

 

They said possible particle streak the first time but it shows up on the following test so no longer do they feel it is a streak and are scratching their heads. Only idea at this point is the aggressive tune... it didn't start until exactly after I had it done. Maybe slight detonation?

 

could be a possibility im just making educated guesses though since ive never had this done

 

From what I remember correctly the first layer of a bearing is lead, thwn copper then steel. It's weird that you had copper in the oil before lead

 

Of course you are all assuming the test is accurate and predictive. If you sent 2 samples from the same oil change, I wonder what the range of reported values would be... You might want to ask what they use for quality control monitoring (external control samples etc).

 

The copper appeared after the car had sit outdoors undriven for 6 months including buried under snow for 3 months. My guess on that one was oil cooler oxidation into sitting so long in harsh environment. It slowly went away as you can see..

I guess my final question is what should be expected of a F/I stock VQ in terms of lead PPM's? Does anyone other than me do UOA?