I recently took car to an Indy to fix engine rattle after attempting to replace CPS and Solenoids myself. He showed me some gunk buildup inside engine as shown in video here. He thought I was using low grade gasoline or I was adding some type of engine oil treatment, neither was true.

My drive to work is a little over a mile, and on cold mornings and afternoons, engine doesn’t even reach half way to full operating temperature. Could this cause the buildup, if not what could it be. Car has 56k miles and gets oil changes at dealer every 5K miles. I use Costco’s premium fuel.

 

Sounds like your oil never gets a chance to boil off any water (condensation) present. Time to go for a long drive.

Another point: doing an engine flush treatment as part of your oil change can dissolve gunk. The flush isn't something you want to drive around with in your crankcase, but follow the instructions before dumping the oil and it works well. I do it on my ML350 diesel every so often to stop pudding from forming.

I don't doubt someone will be along shortly to tell you that mine is a horrible idea that will destroy the engine forthwith, but it works for me.

 

Using 91 octane or higher and good quality oil will help with keeping carbon deposits off of the intake valves, but nothing will stop it from forming. You have a direct injection M276 engine. Meaning that the gasoline from the injectors are sprayed directly onto the piston/chamber. Since the gasoline isn't sprayed directly onto the valves (port injection), they get gunked up. Older cars did not have a problem with this, and newer cars like some Toyotas are not doing half port injection half direct injection for this exact reason.

Here is a picture of my valves before and after cleaning them. I change my oil and filter every 3,000 miles. I replace spark plugs every 30,000. 93 octane always at Mobil or Shell, 90% highway miles.


There really is no way around it other than to take off your intake manifold and clean them. You can find hundreds of videos online of people cleaning intake valves. Best DIY remedy i've found (and the best that works for me) is to zip tie a bunch of zip ties together in a bunch and just hammer away the carbon build up using CRC valve cleaner and CRC brake clean (let it soak in the valves for 15 or so minutes). Pick off as much of the carbon build up with a pick, and vacuum the ports. You'll be golden.

Cleaning them also helps with fuel economy and obviously helps with the engine running smoother. It'll help with longevity and sealing the valves as much as possible to avoid leaks in the combustion chamber.

One more thing to add, i've said good engine oil in the beginning for a reason. I would highly recommend using better oil than what you buy at Costco if you plan on keeping the car long term. Use Mobil 1 European formula or use Genuine MB oil. Either way, it's a good thing you're changing every 5k miles.

 

Definitely clean that up. If you drive that short of a drive you need to purposely drive more and once in a while give it the old Italian tune up. I blow out my cars once a month. Usually getting into a on ramp. I have never in my life had this issue in any car.

Use high grade gas and change oil every 5k miles.

 

while you’re not wrong, comparing a diesel and a gasoline direct injection engine is very different.

diesels unlike gasoline engines use exhaust gas recirculation (EGR) to lower its engine emissions. This sends raw soot (particles) back into the intake.

the reason why direct injection gasoline engines have carbon build up on intake valves is because the gas isn’t sprayed directly onto the valves. Absolutely nothing the OP, my self, or anyone else does will stop this from happening. It’s unfortunately something we have to deal with when it comes to direct injection engines. Using good quality oil and 91+ octane does help, but it will not stop the carbon build up.

 

Would adding Chevron’s fuel treatment additive help reduce the gunk?

 

No. Nothing you pour in or do will get rid of the build up. The reason for that is because nothing sprays onto the intake valves. You will have to manually clean it, or have someone walnut blast it to remove it.

whatever you pour in the gas tank or oil, it’ll just go straight into the piston, not the intake valves.

 

This is not bad for a GDI engine!
Cleaning your intake valves won't make the engine run any differently.

The same setup that's causing this is also causing the startup rattles.

You're doing well with 5k.Mi oil service - The oul deposited look fresh & clean (instead of burnt black into sludge).


Cyl.#4


Cyl.#5


Cyl.#6... pretty nice looking

We can see a fair amount of oil is being vaporized out of the crankcase, through the ineffective PCV system working as designed (not failed).

Instead of dealing with valves now... replace your dirty LAMBDA and PCV + HPFP near the 100k.Mi mark.

 

OP really should clean his valves. The dirtier they get the more at risk he will be of his intake valves not seating properly with his cylinder head. It's better to clean his valves for $25 using brake clean and zip ties than having to get his valves and cylinder head lapped by a professional for a couple of thousand dollars.

It will also improve his MPG and his engine will run more efficiently.

Think of your intake valves like veins that go to your main artery. If you have veins that are clogged up, not enough blood (in this case, air) is going to the heart (in our case the pistons). Your engine will idle better, it will have better throttle response, and it'll be roughly 3+MPG better in city and highway combined. I know I went from getting about 25 MPG on the highway (about 430 Miles on a full tank) to about 28-29 MPG (about 500 miles on a full tank) after cleaning my valves on my W213.

 

Valves cleaning near 100 to 140kMi maybe but now valves are visibly shinny.

These two huge intake ports per cylinder are not going to affect the AF mixture.

I get between 29 and 33mpg on flat Hwy reported as "500Mikes range" per tank.

My engine's nearing 80k.Mi with intake GDI valves looking just like Op... no problem!

 

I respectfully disagree. I had 80,000 miles on my W213 with immaculate service intervals and 90% highway driving and you can see from my picture in my first reply to OP that I had a lot of carbon build up. Not to the point where it would do damage, but definitely in the "need to clean" area.

You can also see in OP's video that he has a lot more carbon build up than I did in my picture. He could and really should clean out his valves now. Again, the biggest problem isn't a problem right now until it becomes a problem= Valves not seating properly to his valve seats. It WILL happen if too much gunk gets on his valves.





If anything, he will benefit from better idling, better MPG's, and a healthier breathing engine. To each their own though. I now have 160,000 miles on my W213 and it's running like brand new *knock on wood*

 

FREQUENT SERVICE...
how many times did you get your intake valves serviced to reach 160k.Mi?
It's not bad to clean valves, just not mint is ok too.

MISC SERVICES...
any replacement of oil separator to slow down oil migrating to your intake?
Your intake has no oil, only valves do, right?


SIGNIFICANT...
The topic of burnt oil deposit is significant.
Valves should not be the main focus.
The valves are only a marker of what's happening to the oil flying out...
Cleaning valves early on is a drop in a bucket.

How about your combustion chambers & pistons tops: how clean or crusted?

This is shown to groove cyl. bores to drop compression and cause blow-by pressure.

 

The bigger problem here is that he only drives a mile after a cold start. He needs to install a heater on his oil pan or walk to work.

 

Once at 50,000 miles and I just did the cleaning again at 120,000 miles or so. You can see carbon build up as little as 20,000 miles on DI engines.

What? Just not mint is ok too? You're saying a clean engine is not okay and not healthy?

I don't think you understand how DI engines work... Even if you have a brand new PCV system or replace your PCV every 20,000 miles, you will still get carbon build up on your valves in a DI engine. No matter what you do you WILL get build up. No gas is spraying on the valves like port injection cars do. Port injection cars have clean valves because they spray gasoline directly on the intake valves. DI engines spray directly into the piston. Therefore you will have build up of carbon no matter what.

They're clean as a whistle. Every DI engine piston tops and combustion chamber should be clean for the most part, unless you have coolant and oil mixing or you're running too rich or too lean....


Leak down test in all cylinders show 1-2% loss at 100PSI for 5 minute test intervals. Compression tests show roughly 1-2% difference between each cylinder. Again - your cylinders will be okay if you change your oil every 5,000-10,000 miles and use good fuel. Your intake valves are the only part of the engine that WILL build up carbon and junk.

 

I agree that there is nothing worse for your engine than short drives and not allowing the engine to warm up sufficiently before driving off/beating on it.

OP should def drive it more on the highway or at the least, do more frequent oil changes if he's doing short trips. However, the valve problem he has will still be present either way. Just more volume of carbon will be present from frequent shorter trips vs highway runs and pulls.

 

I did have the shop clean up the gunk while they were at it, and they also replaced the PCV. Yes, engine is not getting hot enough, I'll have to get a different job a bit far away

 

When you do that, I assume you go for the closed ones...then rotate the engine to get a new set of closed pistons?

 

Just map out a way that allows you to drive a little bit more to your destination.

 

Very good decision. Sooner or later you'll have to do it. Better to do it early on before any major problems arise and before you have to spend $2,000 - $3,000 for someone to remove your engine head and re-lap your valves to your block (super tedious and expensive work).

You don't necessarily have to go anywhere further. I would say once a week take the car on the highway and just drive it normally for 10-15 minutes. On the on ramp give it a little bit more juice (don't have to red line it, just go up to to 4-5,000 RPM) and you'll be okay. Either way, it won't really help your valves stay any cleaner than just driving it around town 24/7.

 

You HAVE TO clean with the valves closed. If you don't, you'll introduce brake clean, carbon deposits, gunk etc into your combustion chamber.

What I do is look up at the firing order of my cylinders. On my W213 4 cylinder, it goes in the order of Cyl 1 ---> Cyl 3 ---> Cyl 4 ---> Cyl 2.

So I would start with Cylinder 1, make sure the piston is at TDC (Top dead center), and then turn my phone camera (or better yet if you have a borescope camera) and look if the intake valves are shut completely. Once I clean the first set, then I rotate the crankshaft another 180° and that should make the next cylinder in the firing order have closed valves (in my case, i would work on Cylinder 3 next).

Make sure you are removing ALL of the carbon deposits from the intake valves that you remove. Last thing you want to do is have that crap go into the piston. I like to tape a Jerryrig a stray/pipe of some sorts to my vacuum to be able to get into the tight spaces and clean everything up.

It's honestly not that hard to do. Just need to have patience because it sometimes feels like it's concrete thats soldiered onto the valves, and not carbon.

 

I typically use 10 or so heavy duty zip ties, and bundle them up/zip tie them with one zip tie together. I use the pointy end of the zip ties to basically move in and out of the intake valves after letting them soak in brake clean for 15 minutes. It's a good tool to use since they're plastic and sturdy. They won't damage the aluminum.

 

I have heard that short drives are not good for the engine as well. Luckily , you have discovered that . I think it would be worse at the higher miles . Italian tune up looks fun and cool but I don't know whether or not it's worth it

Happy Driving

 

Italian tune ups are only good for the soul 😂

 

Just pick up a few shifts as an Uber Eats driver on the side, get the engine hot enough and make a little money

 

doesnt uber eats require you to provide your VIN number of the car you’ll be using? I’m pretty sure they then send that data somewhere and next thing you know your vehicle is registered as a taxi/delivery vehicle (at least that is here in Connecticut)