Yep. Using detergent cleaners (Techron) on your injection system isn't a bad thing. It just won't solve the carbon issue. I know people like to put in additives but I know that in California and Nevada for sure all of the major companies use some sort of detergent in thier gas. So, I don't worry too much about it.
Meh, I'm still kind of miffed about the whole thing. I drive for about 65 miles round trip every day on the highway with plenty of opportunity for hard pulls and cruising. At 46,000 miles I've had no misfire issues or sluggish engine response. Then again, I've seafoamed my intake tract every 5000 miles since about 25,000 miles on the clock. Basically before every oil change. I'm hoping this is helping the issue but I haven't had a chance to look in my intake ports yet. It's a major inconvenience knowing that if you want to do a great job of cleaning everything out you need to pull the head along with major labor and special tools (cam timing) to alleviate something silly like this. The other alternative is to try and scrub the ports carefully with some type of brush, solvent, and a vacuum pump. I really love the characteristics of the Prince engine, but this is such a pain. :mad2:
Does anyone know if this is an inherent problem with all DI engines? I don't hear about this being a problem with other DI engines.
I have heard that it is a problem with other direct injection gas engines. Sooner or later somebody has to find a fix for the carbon issue. As for now I am very afraid of the Prince of an engine. There have been changes for the 2011 model, but the jury is still out on the latest fix. The Justa R56 is not direct injection & shows none of the problems the R56 MCS has.
There seems to be some issues in VW-Audi land too. VWVortex.com - Direct injection causes intake valve buildup?
Until they add a fifth injector inside the intake manifold to clean the valves it's always going to be a problem. I'm pretty sure Toyota has already done this. The other alternative would be water/meth injection, but that brings tuning issues to the table. Again, what a pain!
Check this article out. It's a fantastic breakdown of DI and how the carbon buildup affects cars. Sounds like early DI engines are particularly sensitive, before they figured out how to re-route PCV valves and EGS lines and alter the combustion. Case study is an RS4 that loses 1 hp every 500 miles. Direct Injection Fouls Some Early Adopters - AutoObserver
Ford is already doing this with thier direct injection motors. Each DI injector has a secondary one behind the valve. There was supposed to be another advantage to efficient fuel consumption as well but I'm gonna guess it mostly has to to with the build-up from PCV. I have a friend who is an Audi Mastertech in Vegas. He is seeing the carbon build-up on thier DI motors. He says it's worse on the higher performance cars. (EDIT: Just saw the post BThayer23 put up... ) I'm in a smilar boat to you: I just passed the 42k mark with my 2010 MCS. I drive about 60miles round trip everyday and I'm a pretty "spirited" driver. I'm not showing any signs of build-up. No valve chatter on cold start-up. No hesitation on acceleration. Still feels good. Though, I've never seafoamed the intake. My Dad has an '08 MCSa and he IS seeing these issues. He has 38k miles. But he does a bunch of short trips. So engine isn't run too hard and not often to full temp. I told hime to start complaining to the dealer. The service guy we have said he can get it done for free. He just needs 2-3 trips into service for those issues before the service manager will okay the intake cleaning as "Dealer Goodwill" (read: Free).
Coincidence?? Took the Prius in for service and along with other issues they suggested that I consider this service "Fuel/Air Induction System Clean-Up Service" from BG Products. The brochure is here. So even a 75hp 1.5 L engine can have problems?
Is the Prius a DI engine? Could it be that the service suggested was just a cash cow for the dealer & possibly not needed?
Toyota calls their dual injection system "D-4S." The new Toyobaru concept car will use a 2.0 Subaru boxer engine with the D-4S injection technology, too. From the Toyota GR engine Wikipedia article:
Yep.:crazy: Actually, displacement and HP have nothing to do with it. It's a matter of PCV (Positive crank-case ventilation) recirculating vaoprized oil and particulates that build-up on the back side of the valve because there there is no fuel spray hitting the back of the valve in direct injection that can help clean it off. So your 400+ HP 4.2l V8 in your RS4 or your 75 HP 1.5l in your Prius are both susceptable to to the issue. (Assuming the Prius gas engine is actually DI; I don't know anything really about Priuses)
New member here, and experience with this exact situation is what led me to the forum in the first place '10 MCS with about 22k miles when the Check Engine light popped on. Dealer told me it was from excessive carbon build-up on the intake. They did a good will cleaning and gave me the same bit about poor fuel quality and adding Techron. I followed up with some questions to the service adviser as to how that would make any difference in a DI system? Eventually they admitted to me that MINI was aware of the issue, but did not have a viable solution for it. I'm considering the seafoam treatment on the intake before every oil change, and possibly even an oil catch can(though the idea of needing to install hardware under my hood to correct a design issue is absurd to me). I saved the emails where the adviser says that Mini knows about the issue, so I will keep them in case I have to go back for the same cleaning process and I get stonewalled. All-in-all, it's a pretty poor situation if you ask me.
Much appreciated. This article is most enlightening and confirms lots of past suspicions. Let's hope that the reengineered PCV routing on the N18 was done in response to an actual corporate awareness of the need for MINI to address the problem, and that the redesign was done in a manner that is fairly effective at mitigating the issue. I hope, I hope.
I'm at 47,XXX miles now with my 2010 and I haven't had any issues. While speaking with my SA the last time I was in (about a month ago) he and I talked about the issue. He seemed to observe that cars that he could confirm were driven to temp AND driven hard (spirited some call it) had no issue. It was the long lopy highway miles at low revs and no boost that showed issues in the 30k+ range and the short cold trip cars that showed sooner than that. This is based on his observations though and certainly don't denote absolute fact. As far as the seafoam or other water treatments: from what I've heard it helps a bit but once the carbon had bonded it's REALLY hard to remove chemically as it's become very inert/unrreactive in such a base chemical state. SO it might slow the process but not stop or reverse it. An oil catch-can makes sense to me but I haven't seen any good long term comparo's to say it's a solution or not. It's not going to get everything that the PCV valve dumps back into the intake it should collect a big % of it. Beam, thanks for posting your experience. I'm glad your dealer performed the valve cleaning. You might want to pop over to the new member introduction section and introduce yourself and post some pics of your ride.
So, Saturday I had my intake carbon cleaned by MINI of Monrovia. I asked the tech to take a few pics. He did and e-mailed the attached pics to me. He wrote in the e-mail: "Cyl1 was the worst at level 4 carbon build-up. Cyl4 was a 3. Cyl2 & Cyl3 were both 2s. I only took a picture of Cyl2 since they were the same. This is on a scale of 1-9. 1 is clean/new car. 9 is a non-functioning engine." I spoke with my SA and the tech when I went in to pick-up my car. He was actually working on a 2009 MCS with 24k miles. It had Level 8 build-up on the 1 & 4 cylinders and level 5 on the 2 & 3. Apparently the engine was throwing misfire codes and obviously running like crap. It does look like how the vehice is driven and cycled that will effect how quickly the carbon builds-up on the valves. Short-trips where the engine doesn't get to full temp and run at temp for a while (typical short commute to work) expedites the effects. There is no real way to stop it. It can be deterred for longer periods of time with correctly placed catch cans and driving habits that run the engine to temp and keep it there. Less substantiated is hard driving (Autox & track days) seems to help as well but unfortunately I don't have enough reference points to make an anecdotal observation. For reference here is a summary of the condition of my car and the driving habits at the time of cleaning: -2010 MCS Manual -58,653 miles -ECU Reflached by MINI of Monrovia with a tune that was intended to reduce carbon build-up on manual MCS with N14 engines @ 31k miles -Daily commute 30 miles one-way (60 miles a day; 5-days a week) with approximately 30 minutes of driving at 65-80mph -Rev-match down-shifts -8 full track days (High revs for 20-25 minute sessions; 5 sessions/day) -26 Auto crosses (high revs for short 30-60 second bursts while at op-temps) -Oil changes performed on "half-cycle" intervals (ususally around 7-8k miles) -All other maintenance performed per MINI USA recommendations -Chevron 91 octane fuel used at all times. If you take a look at your intake at any time please post-up pics and list what the condition of your car is as I have above. Collecting pics and reference points would helpful to everyone.