Banks Running at different richnesses (13 Cali)

I have a Cali 30 just a couple of weeks old and have to admit I was surprised with the 12,500 mile service interval. This may end up being a part of the problem. I did a lot of research on oil in the 80s and pretty sure not a lot has changed even if the marketing does sing the praises of the synthetics. The part of the oil that is synthetic is the additives. Typical oil additives last for 40-60 operating hours are rated temperature. Pushing oils past their native operating temp will lead to aggressive degradation of the oil molecule even if the additives still test out as acceptable. Oil additives make the oil perform like an oil that it is not for a period of time. There is a great video on YouTube called "Oil in your engine". Anyone who has not watched it before should watch it. Long before there was a YouTube I had the original VHS tape I ordered from BP. These engines can generate localized temps that may be quite high. The aluminum does a great job of dissipating the heat but does not stop the heat at the point of combustion and that seems to be where the carbon is depositing.

Not sure if many here saw the article but back in the late 70s the Wall Street Journal (I think) did an extensive article on oils. GM had extended their service intervals to 7,500 miles and later started buying lots of engines for customers. They went out and bought off the shelf about 220 different oils and ran their own tests only to find that only 14 actually met the specs stamped on the lid of the can. Since they could not get the oil industry to produce oils at the specification on the can, they reduced their intervals back to match the oil they found to be the most common. I hope the Ferrari techs take a good look at this problem to see what the cause is.

On the other hand there could be some impurities in today's fuels that may be manifesting themselves during the higher operating temps in these new high performance high efficiency engines.

 

FWIW, This is the first Ferrari I have seen that has anywhere near these miles on it in the short timeframe.

I agree 12,500 is pushing it, but the reality is that the services on 99% of the cars we are time based ( 12 months ) with minimal mileage, usually under 1,000.

To answer your question directly, an opinion would be that it's related to the direct injection design, that has been discussed all over the forums ( Audi, Lexus, BMW, etc ) Since the fuel spray is no longer coating or " cleaning " the port or valve bell area, it's allowing the build up to occur. Hence, why additives or cleaners, have minimal impact, as they are also being sprayed directly into the cyl rather than ever touching the valve it's supposed to be " cleaning " ( maybe some vapor of the cleaner back flows somehow ? )

Thank you for your post!


S

 

S - Thanks for your input. I am a bit more than curious on the matter since I will be enjoying driving my Cali as well. I picked it up at Boardwalk 2 weeks ago. Of course I drove it back to Alabama which accounts for 650 of my 1,700 miles on the car. I am sure in a few weeks I will start rotating driving my Lexus IS-250C and the Cali but it is easy to see 10k per year in a car that is so amazing. So, I might be in his position in a year as well.

Carbon buildup invites 2 questions - the source of the carbon - is it from oil oxidation which would be attributed to the oil getting too hot or is it from unburned carbon in the fuel combustion. That is the only 2 sources for carbon. If it is unburned fuel then it does go back to either the fuel / air mixture or the combustion zone dynamics. In either case it should show up in reduced performance. This type of carbon I would suspect would be layered and hard and would be scraped off in flakes. Oxidized oil residue build up would appear more like a thick tar I would suspect and would have minimal effect on performance other than the sticking or blocking the air and gas flow through the valves.

Does this make sense or what are you seeing? I have never disassembled a Ferrari engine and it has been years since I took any engine apart but as an engineer I am a specialist in coal fired boiler combustion and while a power plant boiler and a car engine are vastly different it all comes down to fuel and air and combustion with reactants and products. Basic thermochemistry.

 

To answer your immediate question, the build up is a thick tar like material.

.. and you obviously have a better handle on thermochemistry than I do, so I will defer to you and if there are questions I may get answers to for you, I will do my best!...

AND by all means, PLEASE enjoy your Cali 30!

S

 

I have driven BMWs for almost 30 years and have been discussing those cars with other BMW owners and expert mechanics for most of that time. The issue of carbon buildup in direct injection engine is very well established… BMW shops have special products and techniques for dealing with the problem on a regular basis. This problem is an old, very well-understood one that affects direct injection engines.

AFAIK, it is not an issue with the oil, the carbon deposits come from incomplete combustion of fuel. As the problem worsens, the engine will run rougher and you will also experience hesitation upon throttle application in the lower gears. Effects on highspeed acceleration is harder to detect. The engine will lose power, as if it badly needs a tune-up.

 

I have a 2012 car here for injector rail replacement as well. Car has a consistant miss above 5k rpm on cylinder 4. Swaped coils and plugs to other cylinders and still the same. Compression was good and so was leakdown. Last thing is injectors. Gotta buy the entire rail assembly which is expensive, but not out of line, considering how much BMW injectors cost.

 

How much does it cost and is there any preventative medicine ?

 

The rail is 2700 cnd. Plus intake gaskets. There is no preventative medicine, other then to drive the car as intended. Direct injected cars are really becoming a problem of us guys in the service industry. The amount of "coking" on the valves and intake ports is getting insane. I have had to remove heads on the bmw's and have them sent out to be cleaned. Some of them are coked up so bad, it's amazing the car will even run. I wish I had pics to post of how bad they can get.

With direct injection, you no longer have the cleaning effect of the fuel hitting the valve on the way into the cylinder. The result is really bad. Valve jobs were thought to be a thing of the past, but now they are the word of the day.

 

Btw, injector cleaner will have zero effect on keeping the valves clean, and honestly I don't know if they will have any effect on a direct injected car at all.

The coking of the valves is a result of many different things. One being oil. Valve guides are lubed with oil and a minimal amount of oil will get past the seals. This oil will cause coking around the base of the valve stems., the other is an ineffective PCV system. Any oil entering the intake manifold even slightly (which is acceptable) will be pulled into the intake ports, making more carbon build up. Carbon is the result of oil being heated to the point of a solid. The stuff that doesn't get burned off, results in an almost concret like black gunk on the back side of the valves and intake ports.

I have tried to clean this stuff out in the past, and you need a hammer and a punch to do it if it's bad enough. We even bought a portable beed blaster to try and clean the ports out. It works, but if it's really bad, the head must be removed, and disassembled.

Power and fuel economy has it's price no matter what you do.

 

taking the car out on the hwy and letting it rip, will that blow out the cake ?

 

When I first started driving BMWs I had injector and valve problems, even needed the walnut shell treatment. The mechanic (who was a certified M5 mechanic) suggested I use a fuel injector cleaner every 2-3 months. Problem went away after that and I never needed expensive garage injector or valve cleaning again. No hesitation, power loss issues after injector treatments.

Injector cleaners do work, depending on which ones you use - Wynn's, Jectron, Techron all work. STP did not work for me. And yes, driving your car hard (high rev) regularly on longer trips (40-60 minutes) will also help.

My trick was to mix 1/2 a tank (or less) of gas (instead of a full tank) with my Wynn's in my BMWs - and drive it hard until the tank was 1/4 or less before filling it back up and getting an oil change. However, I just don't have enough FCar experience to recommend this for FCars. But with BMWs, regular use injector cleaners is absolutely de rigueur.

BMW even resells their own re-branded injector cleaners. High quality fuel will contain some injector cleaner as well. These people don't do this just to waste money. It probably costs BMW more to inventory and sell injector cleaners than they can make on the slim margins. BMW makes money by selling cars, not snake oil.

 

do you use both at the same time or 1 per tank every 6 months ?

 

is the wins better than this ? or is this fine ?

 

Marvel Mystery oil....

 

No, you should only ever use one type of injector cleaner at a time… and I would not use them on my Cali at all unless the garage says the car could use the extra treatment. I used them on my BMWs because I drove them for over 15 years and it was de rigueur to use such cleaners on BMW engines. I took some risks with my BMWs that I would hesitate to take with an FCar.