Walnut Blasting Intake valves to clean carbon build up.

[@thirdgearboogie2210]

Good Work!

[@angelocardoc]

Great video. A catch can on the PCV system would help prevent some of that carbon buildup.

[@theoffroadingmechanic]

The Honda fit just doesn't have an oil separator in the valve cover like the other earth dream motor the pcv comes from the crank case below and runs a hose up to the intake manifold. The valve cover just has the fresh air side of the vent for the PCV system.

[@Max_Thunder]

I will need to do this on my GTI soon. I am at almost 100k miles. I will likely only have to do it once, in my ownership.

[@theoffroadingmechanic]

At least the intake is on the front and not in the back.

[@jrichardson-m9m]

thankfully this intake takes like 5min to remove. quick easy check when doing a 105k service. Way back before this bulletin came out I had one that was all carboned up and we ran a BG intake induction service and we found the fit intake manifold HEAVILY favors cyl 3 and cyl 4. The induction service wouldn't touch 1 and 4 but 2/3 were clean.

[@theoffroadingmechanic]

That's good to know if I do the induction cleaner in the future it will also help in showing how effectively just spraying into the intake with a cleaner will clean the valves. Cuz not all manifolds have a straight shot to the intake ports usually they start down low and have to make its way up the runner and it looks at the bottom and you get a smoke show when you rev it up.

[@jrichardson-m9m]

@theoffroadingmechanic always a good time when the exhaust hose blows off when you rev it up and cloud out the entire shop.

[@theoffroadingmechanic]

Or when I did that outside on a busy road and a cop car pulled up and asked me what's going on I and told him it's a Hyundai.😆

[@jrichardson-m9m]

@@theoffroadingmechanic lol, we had someone pull out and cloud out the entire road once. Got a visit from the local cops. Good times.

[@chrisfreemesser]

You know what pick works really well for this issue? When you pick to only buy cars with port fuel injection 🤣 I've heard that a lot of shops won't do this because of liability issues...they're worried that if they don't get every iota of walnut shell out of the intake that some sort of engine damage can occur. Is walnut blasting something Honda itself approves of?

[@sivucit]

How do we do this who don’t have walnut blaster

[@theoffroadingmechanic]

When I was at Hyundai cleaning intake valves and didn't have the tool I used a bundle of zip ties tied up together and carb cleaner and just went to town on those valves.

[@sivucit]

@ thanks buddy

[@MrSamPhoenix]

Good job. But I thought Honda figured out a way to avoid this issue.

[@theoffroadingmechanic]

Not really. The fit doesn't have an oil separator on the valve cover like the other earth dream motors the pcv comes up from the crank case to the intake manifold and there is only a vent on the valve cover. But every Honda intake manifold I've taken off with direct injection will have carbon on the intake valves. It's just the fit has it worse.

[@MrSamPhoenix]

@ Oh I see, and how does Honda minimize the negative effect in comparison to other engines with (only) direct injection.

[@theoffroadingmechanic]

There's no doubt about it carbon build up is carbon build up. But I'm no engineer but I can give you an educated guess from past experience. Even in the 1.5T when you start up cold you can notice some misfire if you really pay attention it's not very noticeable but it's there doesn't set a check engine light for it. I would think it has to do with something in the software to prolong monitoring misfire counts until engine reaches a predetermined temperature. I say that because back when I was a Hyundai tech and they first came out with direct injection on their engines we were getting misfire but only during cold starts. And right around just over 20k kms these misfire will happen on the engines. A bulletin came out with a software update that remedied it. And I got curious so I checked live data before and after the software update and indeed misfire count when cold starting it goes up and sets a check engine light. Cold started after the software update still misfired but no engine light. But these misfires weren't hard misfires you can feel it if you are really looking for it though. So this is my own opinion and may not be the correct one it all has to do with software and how the computer determines and what conditions are normal for this to happen. You will always have carbon build up on direct injection there's no getting around that and you can minimize it with oil separator but reality is it'll happen. When your intake valve opens and closes they also rotate slightly this cleans off the valve seat if you ever remove an intake valve with direct injection the valve seat and valve will have a nice clean spot all the way around to seal so it's not a sealing issue and more of a flow issue.

[@MrSamPhoenix]

@ Thanks for the info!

[@Chickennss]

I checked our 2018 pilot when adjusting the valves at 100,000 miles and the valve heads were fairly clean. The valve shaft had a bit of carbon on the, but still fairly clean. Cylinder 1 had the most carbon on them of the 6.

[@rustbeltrobclassic2512]

I am guessing this bad design, which i assume is due to the way these new engines are designed, where the direct injection, injector is on the intake valve side that when the intake valve opens it is being sprayed by the injector and the raw fuel not completely being burnt causes the gummed up valves and carbon build up, I just assume the reason it's not on the exhaust valve side is due to heat or knock reasons, because otherwise i would think the exhaust port heat would help with reducing the build up of deposits.. Though i still think port injection, while maybe not as fuel efficient, is still a better idea since the detergent in the fuel cleans the valves.. I am pretty sure they are now making engines with both injector setups to fight this issue,.. really makes me miss a carburetor.. 😂

[@Thankyou_3]

Wow, what a contrast in quality between the Honda Fit vs. Toyota Yaris. Shame on Honda to destroy a prestigious brand and it has brought in uneducated engineers into their R&D. Even Nissan don’t have these quality issues. I used to be a Honda Fanboy in the 80s and 90s but last 15 years or so they are absolutely terrible brand.

[@Crunchymunchys]

When I worked at Mr. Lube (yes i know upsale lube jockies) they had a fuel system cleaning system that would clean the carbon off the back of valves and other internal components that fuel/air or exhaust would touch. If you didn't run the engine at 2k RPMs while inserting one of the parts through the air intake (beyond the air filter and was supposedly safe for turbos and considering how many turbo's i used the product on id say the product was right). it would run kinda of rough while that pressurized can would empty into the air intake for about 5 or so minutes but you could smell some horrible sulfur smell and the exhaust would blow a lot of white smoke until said can was empty. We had a lot of Hyundai and KIAs use the product and they never had to get the walnut treatment like this done as per their word. If you are curious it was a Kleenflo product but im not sure if you can buy it directly from anywhere as I searched for it while I worked there and couldn't find the same product listed anywhere including their own site

[@theoffroadingmechanic]

When I worked at Hyundai when they came out with direct injection around 2012 they already had carbon build up around 20-30k kms and customers were getting check engine light but freeze frame data shows it was during cold start up. they remedied it with a software update that prolong misfire monitor until a predetermined temperature range when it goes away. And I use to clean the intake valves with bundles of zip ties and cleaner because we never had the walnut blaster.

[@HiFiInsider]

liposuction for your honda. lol how many hours does the job pays?

[@theoffroadingmechanic]

The bulletin calls for around 2hrs

[@ashercohen4739]

👍

[@erictsai1165]

You want Earth Dreams? Dream is gonna cost you money

[@theoffroadingmechanic]

Dreaming of another vehicle.

[@frankxu2321]

I thought customer who buys fit won't spend this much on maintainence lol

[@theoffroadingmechanic]

You're talking about the generations before this. Before direct injection.