Combating DI Intake Valve Deposits - Ford Focus ST

[ajwan]

My interest in DI engine maintenance has peaked now that I recently acquired a new 2013 Ford Focus ST!

We all know the pros and cons of DI engines. It certainly sounds like a low sulfated ash, phosphorus, and sulfur (SAPS) motor oil is the way to go. Problem is, there aren't a whole lot of them in North America. We know that Pennzoil Ultra is one of them (that I know of off hand) that carries the VW 504/507 spec for low SAPS.

But are deposits in the intake valve seat and stem really really a concern, especially for a Ford vehicle? The reason I say this is that it seems Ford is at least ahead of the curve when it comes to addressing this issue.

"Stephen Russ, technical leader for combustion for Ford’s 2-liter Duratec DI engine, said that similar to GM, engineers have determined the proper injection-timing calibration to help eliminate the carbon deposits. But Russ also said the technology of injection components – particularly the high-pressure solenoid injectors – has quickly matured, meaning excess valve deposits in most DI engines should become a thing of the past as these improved components are incorporated into production." http://www.edmunds.com/autoobserver-archive/2011/06/direct-injection-fouls-some-early-adopters.html

Not only that, but check out this patent by Ford:
http://www.google.com/patents/US6178944

"A control method and system is described for a spark ignited, four-stroke engine having multiple combustion chambers, each coupled to at least one intake and one exhaust valve, a fuel injection system for injecting fuel directly into each combustion chamber, and an electronically controlled throttle for throttling air inducted through an intake manifold into the combustion chambers. Comprising:

1) Detecting when to initiate an intake valve cleaning;
2) Indicating when the engine is operating in a homogeneous mode wherein the throttle is partially closed and fuel is injected during an engine intake stroke to generate a homogeneous air/fuel mixture; and
3) in response to said valve cleaning detection and said homogeneous mode indication, injecting additional fuel during a valve overlap of the intake and exhaust valves so that fuel is drawn into the intake manifold and subsequently inducted back into the combustion chamber past the intake valve.

Really really cool stuff. So it does look like Ford thought about these deposit issues wayyyyy before our time. Does make me rest easier on the EcoBoost 2.0T design and execution. Don't think it hurts though to stick with a low SAPS motor oil if you want to do your own changes, or MotorCraft.

Thoughts?

AJWAN

 

[skyship]

I think it's an engine worth avoiding if you spend much time in traffic or do too many short trips. Not sure if using a higher quality and octane fuel would help stop the carbon deposits.
The patent and claims made by Ford just seem to be an attempt to put a positive spin on what appears to be a design fault.

 

[demarpaint]

Originally Posted By: skyship
I think it's an engine worth avoiding if you spend much time in traffic or do too many short trips. Not sure if using a higher quality and octane fuel would help stop the carbon deposits.
The patent and claims made by Ford just seem to be an attempt to put a positive spin on what appears to be a design fault.

 

[JHZR2]

Ive been running a maintenance dose of Redline SI-1 most every tank, but changing to 2-cycle every so often...

 

[ajwan]

So then maybe there is some utility in having a FI cleaner (Techron, Redline, Gumout etc) in a Ford DI engine as the a small amount of fuel (with cleaner) is injected between the intake and exhaust cycles.

From the patent, "cleaning operation will occur only during homogeneous operation because a manifold vacuum is needed to draw fuel from the combustion chamber into the manifold vacuum. Such vacuum will typically occur during homogeneous operation, where throttle plate is in a partially closed position".

Andrew

 

[Danh]

As you have the car, advice to avoid it is probably not helpful. I have a non-ST Focus and use Pennzoil Ultra. The points you have made are good, but Ultra also has very low Noack volatility for a mass-market oil, which should help to minimize intake valve deposits.

As Ultra seems to hit the right notes, is readily available and priced competitively, it seems like an excellent choice to me.

 

[jdeare]

I personally think the issue is overblown. You can find tons of people on the internet who supposedly have had it happen, but I've never met one in person and my mechanic claims to have never had to do a cleaning. Not that this means it's never happened by any means.

I personally am doing nothing special. I stick to good gas (Mobil or Shell usually) but I did that before I got a car with DI. I don't plan on using any extra cleaning additives because I don't feel they are necessary.

 

[antiqueshell]

Something else that I don't believe has been mentioned in these threads about DI engines on BITOG forums is that the US has a higher level of sulfur in our gasoline compared to Europe the level in the US is 30ppm while in Europe it is less than 10ppm (usually 3-5ppm). The only exception is that in California the level is only 15ppm.

It will be interesting to see how the issues with carbon and sulfur buildup in CA compare with the rest of the US.


Also YES if a small amount of gasoline is occasionally injected onto the valves in that Ford engine, PEA detergent WILL HELP reduce build up.

 

[WANG]

The fact that Ford didn't spec out a special low SAPS oil for their GDI engines seems to indicate that they aren't too worried. There is so much hand wringing about DI engines on BITOG that you'd expect to see one dead on the road every day.

Personally, I'd just use a good oil, and enjoy the car. A good catch can probably wouldn't hurt, I'd use one for grins.

Congrats on the new ride! I just test drove one and thought it was fantastic.

 

[chubbs1]

Use Pennzoil Ultra (you just can't go wrong for the price) and use regular gas (not premium) and a bottle of techron or Redline SI-1 before each oil change and you will be driving that car for years.

Merry Christmas!

 

[Greggy_D]

Doesn't bdcardinal work at a Ford Dealership? I'd be curious to get his views of what he sees first hand.

 

[pbm]

I had read (somewhere) that the models with the most DI problems were the early ones (Audi etc..) and that Ford and GM had learned from these companies mistakes and had less problems (by design)...

 

[supercity]

Has anyone tried an aftermarket water injection system to remove deposits?

 

[GMBoy]

Look, I have a Cadillac CTS with the 3.6DI engine. All I do is just before each oil change I will spray the intake down and run the engine while spraying a whole can of intake cleaner thru. This is the only way to wash the valves without taking the engine apart. I just turned 79k miles with no trouble at all. Now, my dad has the same car with 60k miles and he has no troubles either and does not clean his intake so maybe GM (and possibly Ford in your case) has figured out how to build DI engines without deposits like you see in Audis and others.

 

[antiqueshell]

I wonder if you could remove the spark plugs and spray the solvent in directly onto the valves this way? Of course you couldn't spray them too much or you would get hydro lock but perhaps use a high PEA detergent cleaner fluid like Techron and soak the carbon deposits over night and then drive.

 

[GMBoy]

Originally Posted By: antiqueshell
I wonder if you could remove the spark plugs and spray the solvent in directly onto the valves this way? Of course you couldn't spray them too much or you would get hydro lock but perhaps use a high PEA detergent cleaner fluid like Techron and soak the carbon deposits over night and then drive.


Wouldn't work because the spark plug hole is between the valves and they would be mostly in the closed position. Good thought process, though. The only way to effectively clean them is thru the intake mixing cleaner with the air that flows over the valves.

 

[skyship]

An intake cleaner might work, but oddly enough you don't get carbon deposit problems if you can drive at a power setting high enough to get the cylinders hot. Unfortunately anything less than 100mph for at least several hours is not going to help much to clean out cylinders of carbon deposits. In theory it requires about 10 hours at 75% power to burn all the carbon out, but most is gone within a few hours.
To give you an example my old Volvo 1.9TD (115 hp) will start to emit a very slight puff of black smoke when you hit full power to overtake after a few weeks of stop starts and short trips. Once a month I do an autobahn trip of about 3 hours on a Sunday and can drive at 100 mph for almost the entire trip, which requires nearly max continuous power (3700 required/4000 recommended continuous/4500 red line).
For the next few weeks the slight exhaust puff at full power disappears, because the EGR (Not cleaned for 50K miles) and pre KAT exhaust box has had the carbon burnt off.
If you live in a city and spend a lot of time in traffic jams, buy a hybrid not an Audi, BMW, Merc or Porsch, as all of the engines were designed for the autobahn and some of the VW injection systems were designed for EU standard diesel fuel, not gum and carbon deposit forming 3rd world standard fuel. I suspect that a fuel additive might help, but DYOR as some of them are just snake oil, whilst others do work. Not sure if you can avoid poor fuel quality in the US but in the EU, BP stations have the best quality diesel.

 

[FoxS]

You don't need to drive 100mph to generate heat.

On the freeway, just drop down a gear or two and / or switch off overdrive.

 

[demarpaint]

Originally Posted By: antiqueshell
I wonder if you could remove the spark plugs and spray the solvent in directly onto the valves this way? Of course you couldn't spray them too much or you would get hydro lock but perhaps use a high PEA detergent cleaner fluid like Techron and soak the carbon deposits over night and then drive.


Seems like a lot of work doesn't it? I'm thinking something along the lines of an inverse oiler might help. But then again if Ford, GM, and others really have the DI issues resolved there should be no need to do anything out of the ordinary. They should be as easy to maintain as a fuel injected engine, and be as problem free, without an extra maintenance. JMO

 

[skyship]

Originally Posted By: FoxS
You don't need to drive 100mph to generate heat.

On the freeway, just drop down a gear or two and / or switch off overdrive.


That's the old Italian tune up, but I don't recommend it because it can overheat the fluid in some gearboxes in summer, so you would need to confirm such a procedure with the gearbox folks before spending several hours in the wrong gear. It's very similar to towing a heavy load, as it can fry the oil in some weaker boxes. If it's OK then just pick a gear that gives you just under max cont rpm for the legal speed limit, I know some folks in the UK that do that to burn carbon off and they say it works well.