[Trainwreck914]

My intake valves were just NASTY!
I'm at 132k miles. And they were really covered in oily carbon. Very sticky

[mediocrechris]

Which model and year was this?

[Trainwreck914]

2011 535i.

[dzz]

You did it yourself ?

[Trainwreck914]

Yes

[Encendido3]

I'm assuming it was never done. I've heard that the N55 needs it done just like the N54, just not nearly as frequently. Wonder if 100k miles is a good time to do it

[BurrNinja]

How does the car run after this job? Id assume 100x better? Also did you notice any rough idle before this job or engine lights?

[Trainwreck914]

Yeah. It's never been done. I've had the car just about a year now. And have done numerous maintenance items that would have cost more than the car is worth if taken somewhere. I would never own a BMW outside of warranty if I could not service one myself. Even if I could afford to have it done by a mechanic, it would probably put me in the poor house. That's the great thing about these cars. They loose so much value in so little time because upkeep becomes expensive. Which in turn works out for guys like me/us.

Just a point of reference. I did a friends clutch on his 2015 Subaru WRX. His throw out bearing was destroyed and ate into his transmission shaft. But since I had his motor out of the car. I did the walnut blast on his engine. 140k miles. Nowhere near as bad. The third and fourth pic is the before. So any direct injection motor will eventually need to be blasted. The question is at just what interval. He has more mileage than me. Owned since new. And is 4 years younger. All highway miles.

[Trainwreck914]

Originally Posted by BurrNinja

How does the car run after this job? Id assume 100x better? Also did you notice any rough idle before this job or engine lights?

Honestly I haven't really driven the car yet. I started it up and just took it around the block after putting everything back together. I didn't really think I had a rough idle. But I had the occasional hiccup. Where every few revolutions I'd feel like a little misfire. Only at idle. It may be placebo effect. But it does feel smoother and more responsive. I'll update once I get a better drive in. But the hiccup is still there. Now while I had it running. I had the twinpowerturbo cover off. And noticed a pronounced rattle every time there was a hiccup coming from my top end. Felt the fuel injector line going to cylinder 1. And there was a "vibration". Have to investigate more. Not sure if it's an injector. As I'm sure they are original. Or possible timing chain issue. Aside from that. The car runs excellent. No dash lights. I address them right away. Had 2 engine lights so far. One was for the vapor canister purge solenoid
Part # 13907636157. The other was for the boost solenoid part # 11747626351. Everything else just preventative maintenance

[Gjohnson7]

Great job man. I did intake valve cleaning with CRC and a wire brushes. I couldn't believe how bad the intake valves were, considering everyone kept saying it wasn't needed.

FYI, I had a bad hiccup and even a cylinder 2 misfire for months after doing the cleaning. One day I was playing with Ista and stumbled upon a Post Walnut blasting procedure. Apparently the procedure is a intake valve stroke learn process that is supposed to be ran after intake valve cleaning. I ran this procedure and have received a misfire code since. Also, don't have the cold start misfire I was plagued with. I ran the procedure roughly a month and a half ago.

[ChiNorm]

OP, what kind of gas do you use?

Thanks.

[Trainwreck914]

I have to look into that procedure. I use Sunoco ultra 93. Usually same station unless I'm out where I can't go there.

[beegeezy]

Originally Posted by ChiNorm

OP, what kind of gas do you use?

Thanks.

The fuel doesn’t touch the back of the valves in a direct injected engine. You could use jet fuel, wouldn’t matter a bit. This is just maintenance for a modern engine.

[ChiNorm]

Originally Posted by beegeezy

The fuel doesn’t touch the back of the valves in a direct injected engine. You could use jet fuel, wouldn’t matter a bit. This is just maintenance for a modern engine.

Then where does the carbon come from?

[beegeezy]

Originally Posted by ChiNorm

Then where does the carbon come from?

Primarily the EGR system (oil vapors).

[Trainwreck914]

Just wanted to update. I noticed today that my engine "stumble" is gone. I'm not sure if it went right away after the blasting. Or gradually got better. But after about 1000 miles of driving I noticed it today that it has completely stopped. I haven't done any other maintenance since the blasting.