I finally got my 2015 running again after some extensive (to me) repairs that I did at home in my garage. At some point in there I popped off the intake manifold and had a peek at the intake valves.
They were pretty nasty looking after 130k+ miles of my typical spirited driving (including several track days and many more fun days driving to ski resorts on snowy mountain roads).
They all had build-up, but some of them less so than others.
By this point, I was having a myriad of issues including misfires, blown out spark plug threads, and loss of performance. Now I can't attribute all of those symptoms to gunked up valves, but I'm sure the valves weren't helping anything.
I generally followed the set-up described on the Focus ST forums here: https://www.focusst.org/threads/how-to-walnut-blasting-intake-valves.119770/
A few key differences in my approach:
The blasting itself was straightforward. I highly recommend using an air compressor with two outputs - one for the walnut blasting, and another with a basic air gun attachment to displace the stubborn bits of walnut that don't want to be vacuumed up. Otherwise if you only have one output/hose you'll have to relieve the pressure, switch tools, set the pressure, blow some air, relieve the pressure, switch tools, set the pressure, blast some more, relieve the pressure, switch tools.... it goes much much faster and you're less likely to cut corners.
I didn't take a picture of the blaster or the air gun in-use. But they go into the hole on top of the adapter. Nothing complicated.
Each valve got repeated walnut blasting followed by blowing out the walnut with compressed air with the shop vac running the whole time, until I was satisfied with the results.
Here is a side-by-side of before and after I cleaned the first two valves.
All in all, the walnut blasting process itself was tedious but not difficult. I think the hardest part is removing the intake manifold due to everything else that needs to be removed along with it, but between YouTube, forum posts, and service manuals, that part of the job isn't too bad either.
Performance-wise, it feels like a new car again, but like I said earlier there were so many issues that it's hard to gauge how much these valves were hurting things.
I'm no expert, but I've been learning a ton over the past six months (how can anyone afford a mechanic these days!?) and I'm happy to answer questions or go into more detail about any part of it if I can. Hope someone finds this info helpful!
They were pretty nasty looking after 130k+ miles of my typical spirited driving (including several track days and many more fun days driving to ski resorts on snowy mountain roads).
They all had build-up, but some of them less so than others.
By this point, I was having a myriad of issues including misfires, blown out spark plug threads, and loss of performance. Now I can't attribute all of those symptoms to gunked up valves, but I'm sure the valves weren't helping anything.
I generally followed the set-up described on the Focus ST forums here: https://www.focusst.org/threads/how-to-walnut-blasting-intake-valves.119770/
A few key differences in my approach:
- I used a lot of frog tape to cover up ports I wasn't blasting. I also used it to cover up any other holes (vacuum lines, bolt holes, etc).
- I didn't bother laying down blankets. I'm not too keen on keeping things show-ready, it's just not my style! If you want to keep things clean though it's not a bad idea.
- I used a custom-made adapter similar to the one linked on page 2 of that same thread: https://www.ebay.com/itm/Ford-Focus...-Cleaner-Walnut-Blasting-Adapter/113708286072
The blasting itself was straightforward. I highly recommend using an air compressor with two outputs - one for the walnut blasting, and another with a basic air gun attachment to displace the stubborn bits of walnut that don't want to be vacuumed up. Otherwise if you only have one output/hose you'll have to relieve the pressure, switch tools, set the pressure, blow some air, relieve the pressure, switch tools, set the pressure, blast some more, relieve the pressure, switch tools.... it goes much much faster and you're less likely to cut corners.
I didn't take a picture of the blaster or the air gun in-use. But they go into the hole on top of the adapter. Nothing complicated.
Each valve got repeated walnut blasting followed by blowing out the walnut with compressed air with the shop vac running the whole time, until I was satisfied with the results.
Here is a side-by-side of before and after I cleaned the first two valves.
All in all, the walnut blasting process itself was tedious but not difficult. I think the hardest part is removing the intake manifold due to everything else that needs to be removed along with it, but between YouTube, forum posts, and service manuals, that part of the job isn't too bad either.
Performance-wise, it feels like a new car again, but like I said earlier there were so many issues that it's hard to gauge how much these valves were hurting things.
I'm no expert, but I've been learning a ton over the past six months (how can anyone afford a mechanic these days!?) and I'm happy to answer questions or go into more detail about any part of it if I can. Hope someone finds this info helpful!