Petza914

Good plan. It already has Moly in its formulation so you won't need to add anything extra either.

onnastick

This is only my second UOA. I decided to try out SPEEDiagnostix, so since there's no history I'm cross-posting my first UOA. The consumption is pretty low I think (I was nearing having to add my first quart at 1200+ miles). The numbers look pretty good to me, but then again I'm not putting on a ton of miles as I'm not driving as much as I imagined I'd be. Closing in on my first year of ownership of my first Porsche.

The SPEEDiagnostix analysis was on Driven DT40. The Blackstone one I don't actually know since I didn't have that oil put in. I am assuming the previous owner (or dealership) just put in the Porsche recommended Mobile 1. I am now driving it with Driven FR50.

TerrestrialFlyte

I’m definitely not an authority, but the first thing I look at now is Fuel Dilution. Yours is high, if this is an 06 like the unit ID on the Blackstone report suggests. The reason I look at that first is because I have the same problem. I posted mine a few weeks ago (6 October), so you can look there for troubleshooting tips. But I’m sure Petza, silver_tt, and/or Charles will chime in with their input.

onnastick

Thank you for drawing my attention to that. According to Blackstone, the average (I guess for all engines?) is 2.0 and my two numbers were <0.5 and now 1.5. I guess I'll keep an eye out for if the trend continues upward. I have no idea if the original fuel injectors are in there or if one of the three previous owners had them replaced. Unfortunately I purchased it from a dealership without service records. I realize bad spray patterns and other things from bad fuel injectors could increase this number (not to mention my behaviors). I recently started to add Driven Injector Defender every few fill-ups.

silver_tt

As discussed above, Blackstone's fuel dilution number should be ignored. It is actually very bad because it is giving people false information due to using an approximation that is complete garbage.

Agree that 1.5% is high fuel dilution and too high for a 2006 port injected engine.

One improvement that could be made for all of these oil analysis companies is if they ask if your engine is direct injected or port injected on the oil sample intake form. Then "calibrate" the green check mark (talking SpeeDiagnostix here, again just ignore Blackstone's value as it is meaningless and misleading) to < .5% if port injected and < 2% if direct injected. For example, Blackstone shows <2.0 in the "values should be" for Fuel % no matter if your engine is direct injected or port injected.

Petza914

The Driven Carb Defender is a great ongoing preventative maintenance treatment.

I'd recommend you run a full bottle of Redline fuel system cleaner in a half tank of gas. I have a 120k mile Audi Q5 that was throwing a cylinder 1 mixture imbalance code every week. I ran the Redline cleaner in a half tank and another bottle in the next full tank and the code hasn't returned in 5 weeks. Thought I was in for $800 worth of injector replacements, but may have been able to circumvent that for $25.

onnastick

Thanks for the advice, will do. I haven't had any CELs come on that I've noticed.

plpete84

The Redline stuff is really good and was recommended to me by Lake Speed because of its very high PEA content - one of the highest you'll find. I did notice that while using it, my car would puff smoke on start-up. Once I filled up the tank with just gas the smoke on start up went away. I assume it was doing the cleaning and perhaps burning off some dissolved gunk or carbon.

TerrestrialFlyte

From my understanding that CEL comes on a good while after your fuel trims are out of wack.

Here’s a pretty informational video by LNE if you want to understand it better. He covers several models, but does discuss the 997.1’s fuel trims. To some this may be rabbit hole material, but I appreciate it and somewhat understand it.

Carreralicious

I think you can overdo it with the injector cleaners too though. There was a period this past year when I used Driven Injector Defender a couple times in a row (after each fill up) thinking it would clean out the injectors better and then I got a CEL pointing to a bad Evap purge valve. This was right after putting in the 3rd treatment of injector defender. I think it broke off some carbon sediment or something in there and clogged the darned EVAP canister. Replacement cleared the codes and now I use injector cleaner sparingly.

silver_tt

I have been giving more thought to these oil analysis results with ridiculously high fuel dilutions (and conversely results with extremely low values). I can't imagine that M1 5W-40 with 10K miles on it and almost 4% fuel dilution would still have a 11.7 cSt viscosity. Also want to point out that at 3.7%, if it was really true, you should be able to smell it and feel it in the fuel. The wear numbers should be poor too.

As stated I think many of these oil analysis companies must be using very crude measures for this metric, which should be ignored and then you could be missing a dilution problem. Fuel dilution is one of the most important metrics on the oil analysis and can be measured directly with GC or FTIR. FTIR can have short comings in isolation and GC is requires sophisticated algorithms and must be calibrated correctly. But you can use GC to confirm FTIR, for example:
https://apps.dtic.mil/sti/pdfs/ADA347664.pdf

I sent Lake a question regarding this matter and he was kind enough to respond; as part of his response he stated:
We use the GC as the primary read on fuel dilution, and we worked really hard to develop an accurate calibration for the GC. The FTIR is a “sanity check”. We’ve run both and used them together, but I’ve never seen the FTIR show a ton of fuel when the GC doesn't.

When I’m running a report, I look at the viscosity, the GC results, the FTIR results and the engine itself.

One other note is that I reviewed the Speediagnostix intake form (my last test was done in May, been a while) and I see that it is asking for the year and model car the oil sample was taken from. From this information he should be able to determine if the engine is DFI or not (could be some gray area around the time engines transitioned but maybe he has a database or something). Still very important for the owner to understand if they have a DFI engine or not and what the implications are.

silver_tt

Port injected 997.1 showing DFI-like levels of fuel dilution on multiple samples and it's being marked as OK with a green check box every time. This should be flagged and was missed more than once on this particular vehicle............

https://rennlist.com/forums/997-foru...l#post18460217

G.I.G.

Thanks for looping me into this @silver_tt . As you've pointed out, my fuel dilution has constantly been around 1.5 since I bought my car in '19 and started doing UOA's with Speediagnostix. Since you mentioned it, I asked for clarification from Lake and below is his response:

"Thanks for the questions. The fuel dilution of 1.5% is typical for these engines, so you are good. We flag fuel dilution if it goes over 2%.

In regards to the oil consumption, have you considered trying the Driven DI40? Some engines just tend to use some oil, so I would not be worried about it unless it increases."

When I emailed Lake, I was sure to specify that my car was a 997.1 with the M97 port-injected engine. However, he makes reference to DI40 oil which is specifically formulated for DFI cars. Perhaps he is confusing the two?

I don't see as many Speediagnostix UOA's posted compared to Blackstone, and we've already covered why the Blackstone fuel dilution results shouldn't be taken seriously, but it seems as though most of the 997.1 results I see with Speediagnostix have roughly 1.5 fuel dilution, mine included. Both @TerrestrialFlyte and @onnastick posted similar results within the last few weeks as well. For reference, and so we can keep this conversation going on the same thread, below is my most recent Speediagnostix UOA with previous results included. I use Millers CFS 10W50 NT+ oil.




*see my other thread if you're wondering about the tin and vanadium levels* Millers UOA, Speediagnostix vs. Blackstone, and Other Observations

I find it hard to believe, yet not outside the scope of possibility, that all three of us and many others need new injectors, so I'd really like to get some clarity on these measurements and if there is cause for concern. I have watched the YouTube video on why it is important to address fuel trim levels BEFORE a check engine light appears, but I'm also not the type of person who just throws parts at my car as part of a solution looking for a problem. I also asked my Indy a while back if I should consider proactively changing my injectors, and he told me not on my port-injected car.

@Charles Navarro , any thoughts on this?

G.I.G.

I sent Lake another email and below is his response. To help add context I've included the email I sent him.

My email to Lake:

"There seems to be some debate on the Porsche forum, Rennlist, as to what an acceptable value for fuel dilution is dependent on the car and engine. The first half of the 997 generation of 911's have the M97 engine, which is port injected (like mine). Charles Navaro and others feel that with these engines, no more than .5 fuel dilution should be considered acceptable. The second half of the 997 generation received the newer 9A1 engine, which is direct injected. Some feel that since those cars are DFI, that anything under 2.0 is considered acceptable.

I've noticed that other people have posted similar results (~1.5 fuel dilution) with their port-injected 997.1's using Speediagnostix, so I tend to agree with you that it would be considered "normal." However, I'm curious if you have any additional thoughts and if you've talked to Charles about this. I don't think we should all be running out to replace our injectors, especially considering the mileage (most are sub 70k mile cars), but I don't want a bad injector to wash down one or multiple cylinder walls on my car, potentially causing scoring, either. Any additional insight on this would be greatly appreciated."

Lake's response to me:

"Here’s my perspective, the amount of fuel dilution (regardless of the fuel delivery method) is all the engine knows, so that is why we flag for 2% and above. We don’t see any increase in wear with fuel dilution up to 2%, so I personally don’t see any reason to worry about fuel dilution under 2%. The level of .5% is ideal, but we rarely see that.

Keeping the injectors clean with a PolyEtherAmine fuel additive should be the first move if someone wants to lower their fuel dilution."

I've exchanged several emails with Lake today, so hat's off to him for being so responsive, especially on a Saturday. I tend to agree with his response, as my wear metals continue to stay low. I'll probably measure my fuel trim levels and cam shaft deviation shortly just to stay out in front of things. As I noted in my other post, my fuel dilution and oil consumption has remained consistent during my ownership of 3 1/2 years and roughly 15k miles. Until something drastically changes, or I see something abnormal come up with fuel trim levels, I'll just continue to monitor my UOA's and enjoy driving my car.

silver_tt

Lake is very responsive, friendly, and knowledgeable about oil. Thank you for sharing his response (I wanted to ask him more questions but didn't want to keep emailing/pestering him so didn't). Agree with his comments about the wear metals, using PEA (I do this every OCI just before the oil change), and his response about why they flag for 2% and above makes sense from this perspective.

I notice in post #270 jchapura's 2005 port injected also has a 1.31% reading. Looking for a speediagnostix sample for a port injected engine that's under .5% prompted me to contact a good friend who is a professional and a Porsche expert, and he told me his speediagnostix readings also are 1-1.5% in the winter and under 1% in the summer for his port injected Porsche.

Of course some of this has to do with how the car is driven and I should also note that an oil like Driven DI40 will inherently hold less fuel in suspension. But this is fascinating because DFI engines should have higher dilution as reported in the literature. But my DFI 2014 Audi Q5 2.0T running winter blend gas, getting used for short trips to cart kids around only has 1.3% fuel dilution as measured by speediagnostix.

Based on this information I agree that you should just monitor your UOA's going forward, maybe there is not a problem. 997.1s appear to run "high" fuel dilutions for a port injected engine as measured by speediagnostix.

Thank you for the information.