Quote:
Originally Posted by m6pwr
Blankstar43: FWIW I think that's a great report. There is one thing, however, you may want to keep an eye on and that's fuel dilution. It can negatively affect the viscosity or thickness of the oil, and it will also negatively affect the flash point of the oil, making it more likely to vaporize and drop deposits. Your report shows both vis and flash point below the norms for a 6k M3 oil change. Usually when both these metrics are sub-par, fuel dilution may be the culprit.
I know your report shows fuel dilution as nil (<.5%). That's a problem with Blackstone uoa's. They report fuel dilution, but don't really measure it - - they estimate it using a formula that I believe compares the flash point of the virgin oil (if they have it ) and the used oil. My experience is that they can be off. I once submitted a sample from the same drain to a lab that actually uses gas chromatography to test fuel dilution, and a sample from the same drain to Blackstone. Blackstone showed fuel dilution as nil while the other lab (Polaris) showed fuel dilution as almost 2% (what some consider the limit).
It's no big deal, and this is no rant against Blackstone, but if you want to verify fuel dilution, you might use a lab like Polaris that actually measures it.
So if you have high fuel dilution, what can you do about it? Assuming you don't have leaking fuel injectors or some other physical problem with the car (e.g. overly rich mixture), the only other thing you can do is look at how the car is driven. Lots of operation at wide open throttle will add fuel dilution, and frequent cold starts with short trips, and lots of extended idling, will all contribute.
If you want to try an actual measurement of fuel dilution next time, I'd suggest a lab called Oil Analyzers, Inc. They are a private label operation for Polaris. In other words, all the actual lab testing is done by Polaris (ISO accredited for accuracy). Order the kit02 and you will get a test kit that you can send back to OAI (Polaris) by prepaid UPS. So you'll get the results faster than if by US post. You'll also get TBN, oxidation, and nitration included in the uoa report.
http://www.oaitesting.com/index.htm
http://www.polarislabs.com/
Sorry for the bandwidth! |
Thanks for the input and suggestion! I'll definitely send my next samples out for the extra testing here in a few thousand more miles.
Forgive my ignorance, but how can I tell if its something physically wrong with the car and are there any serious side effects/damage that can be caused by high fuel dilution? I do drive the car hard once its warmed up and use it for daily driving (so it might see a handful of trips between 5-25 mile each day on avg), but I don't let it idle more than a couple minutes for the cold start to finish.
I had the BMW dealer take this previous sample we are referring to. Could it be a possibility they let the car idle for 5-10 minutes prior to putting it up on a lift to change the oil and this could be the culprit in this case?