Got to use R2D2 today

[TheBarber]

No, not the droid. It's our roll around media blaster.

This car had 62,XXX miles on it. Cold start misfire on #1 primarily but a smattering of other cylinders as well. Before and after blasting. Ewwwwwwwwwww.

That's about as good as you can get with walnut. Very limited range of motion with the nozzle as well but it did fix the misfire.
It also had a fuel trim issue separate from the poorly sealing valves. 3/4 injectors failed test.

Goodwilled the valve clean and the injectors were under emissions warranty luckily.

Direct Injection is the best!

[jminer]

@thebarber Was it the injectors that caused the buildup and valve issues or something else entirely?

[TheBarber]

@jminer Nope, that's just a byproduct of direct injection. The PCV vapors and EGR gasses build up on the back of the intake valves due to the lack of port injected fuel to wash it off.

I replace a looooot of carbon fouled injectors under warranty. Some cars you can get away with doing an induction cleaner like BG or something but since we have the special port adapters for these engines we use a media blaster instead.

[Roadkilled]

@thebarber That's not R2D2. It's Artie Deco from Hardware Wars.

[gettingoldercarguy]

@thebarber nice before and after pictures

[pip bip]

@thebarber Audi and their walnuts can go fuck themselves.

[Urambo Tauro]

@thebarber That’s a pretty cool setup!

[RacinBob]

@thebarber What brand and engine?

[TheBarber]

@gettingoldercarguy For sure, it’s just going to do it again though.

[TheBarber]

@racinbob This was a L15B1 in a 2018 Honda Fit.

[DipodomysDeserti]

@thebarber I’m pretty sure this is what’s causing misfires on my wife’s BMW, but she has around 140k miles on it. I think her lead foot kept the carbon monster at bay for as long as possible. I had a 335d for a period of time and that guy got a whole new top end at around 40k miles courtesy of BMW.

[RacinBob]

@thebarber Huh, that's disappointing for a Honda. I knew that direct injection had intake deposit issues but had hoped that Honda had addressed them with 5th injector or other means.

In your opinion, how common is deposit issues like this through the current Honda engine families?

[RacinBob]

@thebarber PS, that is why when they offered a Civic LX luxury with sunroof and the 2 liter conventional injection K motor I had her jump on it. Great combination with the CVT. Very good gas mileage (40+) too.

The car hasn't had an issue and I don't expect one as the the 2 liter K in her '02 Si went with no particular maintenance other than annual Mobil 1 changes for 14 years and 200000 miles.

[TheBarber]

@racinbob Pretty common on all of our DI engines. Even if they aren’t registering misfires you definitely are suffering MPG loss. Any of the GDI engines I pull intakes on for misc services I like to peek at the valves and they all have substantial buildup of sludgy carbon which will affect combustion.

Also to be fair any GDI engine from any manufacturer that doesn’t have secondary port injection will have this problem. There is just no way around it. As for why more manufacturers don’t go to the secondary injection it greatly increases fuel mapping complexity, mechanical complexity, and obviously cost.

[RacinBob]

@thebarber said in Got to use R2D2 today:

Also to be fair any GDI engine from any manufacturer that doesn’t have secondary port injection will have this problem. There is just no way around it.

I agree, I assumed that was the reason that Honda and Toyota were late the the GDI party. I knew toyota was a common port injector to clean deposits. I assumed that Honda did too. I guess we will see how reliable their GDI design is.....