I finally cleaned the intake valves today. 72,818 miles, Powell air/oil separator at 52,428. I just used metal picks, Sea Foam, and a gun barrel brush to clean them. Not as thorough like a media blaster would get it, but I got a lot of carbon out. Longer picks would have made it easier. If I have to do this again, I'll get a media blaster. I'd want it cleaner than this. Put a new PCV valve in while at it. Throttle seems a little more responsive, but that could be a placebo effect. I'll see it in my fuel mileage this week. I've been averaging mid 22 mpg each tank lately.

 

I did same as you and will do them again with a blaster as you say. Got mine a little cleaner than yours, did you soak them overnight? It made a difference in mine. Did mine 2 years ago and last winter I looked at them and only had minimal buildup. I'm also running the separator. Nice job!

 

I didn't let them soak for very long. Maybe an hour. It's good enough for me. Glad to be done with it.

 

Yea, its a total pain in the ass to do.

 

they still have a layer of oil gunk on them. should have walnet blasted. its a lot easier than how u did it. just the prep takes a while.

 

That's a lot of work to only do half the job.

 

I agree it's not complete. I don't think pulling the manifold was really that much work, so going back in isn't that difficult. I'll be prepared when I inspect them again in a year or so.

 

ya but ur wasting 20 bucks for a gasket every time. so if ur gonna go in and do it, why not just do it right once and not worry about it again

 

I'll go hop in my time machine and stop myself from wasting a trivial amount of money. If I knew it was going to be so much work for a not-so-great yield, I wouldn't have bothered with this method. I don't mind learning some things the hard way.

 

It works great. You just did a half assed job.

I manually cleaned mine on the now deceased car and mine were just as good as a walnut blast. The whole point is to fill the intake ports to drown all the valves and let them soak for as long as possible. Then, you go to town.

This isn't meant to be demeaning towards you either. I just don't want someone searching about how to go about it and then coming to the same conclusion as you.

Half assed work = half assed results

 

Luckily we've had some members post super detailed how-to's with pictures. They're honestly some of the best community contributed write ups when it comes to DI valve cleaning across most platforms.

Here's a link for people that are searching in the future. https://www.cobaltss.net/forums/how-...emoval-304188/

 

I was unwilling to go nuts with solvent, as I've read concerns about it leaking into the cylinders. Maybe that's an irrational fear as long as the valves are closed completely.

 

Now that is completely understandable. Nothing irrational about that at all, considering liquid doesn't compress

 

I was erring well on the side of caution with this. It wasn't so much a concern for hydrolock (just pull the spark plugs) as I had read it would be bad to wash the oil out of the ring lands. Again, I don't mind doing it twice as long as I don't screw the engine up.

 

I'm afraid to look at this car's valves. I don't think they were ever done and it has 140k on it LOL

 

Guess I had better luck doing mine

I spent a few hours doing them
I used a long flathead to get through the big stuff to start, then I used a rounded pick to get everything out. I soaked my valves in Mazda zoom engine cleaner, then I went at them with a pic, then I sprayed carb cleaner in them, then I blasted the carb cleaner out with an air nozzle. Got great results

Went from this:


To this:

 

Here's a close up of the valve before doing one last blast of carb clean, wiping, then air.

I also wrapped a rag around the flathead and scrubbed with that.

 

No_ss, you didn't walnut blast?

 

Nah man, I just gave you the process I used. The Mazda zoom engine cleaner helped a lot.

 

To be exact on what I used, I used CRC carb cleaner, Mazda zoom engine cleaner. I blasted them a few times with that and let them soak in the Mazda zoom engine cleaner then also with carb cleaner as I cleaned the other valves. The carbon was coming out easy.

 

The hooked pick helped get up by the valve seat and the back side of the valve that would've been hard to get to.

 

CRC makes a GDI valve cleaner that I used when I did mine. Had intention of using the shops media blaster but of course it had to **** out halfway through the first cylinder. Ended up swapping back and forth between the CRC stuff and carb cleaner with picks and some flexible plastic brushes. Ended up with some damn clean valves for doing everything by hand.

Edit: I let the valves soak in the GDI cleaner for a bit before going to town with it and carb clean. It's interesting to watch the white foam it makes turn black and liquify the carbon to the point a rag can remove all but the most baked on gunk.

 

I let mine soak overnight and used various pics, including a round one, and gun cleaning brushes and swabs and mine turned out pretty good.

 

The GDI stuff from CRC is pretty strong cleaner, I've used it on my gdi audi but I can't get a borescope to see before after differences. It would be a good cleaner to use.

 

I used gm top engine cleaner on my ls and it worked great, I really need to do my ss soon. 42k and im sure the previous owner never did it. the stuff from gm works great if let to soak for the appropriate time. Used brake cleaner after a good soak and the carbon disappears. We use it on the 3.6di all the time.