Direct injection

[KRT]

So pretty much every car is now direct injection and the valves get carbon on them bad and cause all kinds of drivability issues.

Bit the bullet and purchased a pretty good walnut blaster. It uses crushed walnut shells and compressed air to blast the hardened carbon off the valves. It has a vacuum wand that catch’s the shells.

2018 Tahoe 5.3 with 80k miles

[KRT]

After

[Greenwing]

Don't see any pics ...

[Colin4]

I see them fine. Looks good.

Sent from my Pixel 3a using Tapatalk

[thunderchicken]

Kevin, do you think ethanol is a contributing factor?

[darealdeal]

Does a catch can help prevent build up?

[KRT]

Kevin, do you think ethanol is a contributing factor?

Not at all.

Direct injection sprays fuel directly into cyl where as before it sprayed fuel over the intake valve.

Fuel, additives, etc have no bearing on this issue.

[ScoobieMcDoobie]

What is causing the carbon to build up on these intake valves?

EGR?

[KRT]

Lots of theories on what and why

What’s known is it’s oil. So the PCV system.

[KRT]

Since it’s my wife’s ride, the 6L80 is out and replacing the torque converter with a billet converter. Even though I deleted the trans T-Sat like the 2nd day she bought it, I’m still scared of the converter. The converters are coming apart and trashing the front pump is what the failure on the 6L’s is. Now the main reason they are coming apart is over temperature but I’m taking no chances.

[Simple Man]

Would have never occurred to me to clean that while in the vehicle. That's why you're KRT.

[KRT]

Here is an Audi we did this week.

[Glenn]

He's the Charlie Daniels of the torque wrench.

[Tater]

Do you work on Innies?

[WoodieSC]

So what would the positive impact be of cleaning this carbon off the tops of the valves & stems, if I'm understanding your pictures correctly?

If the top pics are of a 2018 model engine with only 80K miles on it, I'm wondering what an Land Cruiser 2000 engine with 180K on it would look like. Other than mileage dropping from 16+ to 13.6-14.4 mpg with 80/90 octane fuel, there doesn't seem to be any performance issues. What might I possibly expect, if anything?

Thanks.

[ccleroy]

He's a show off. No, I'm sure of it......I hate him.

[Saltydog235]

So what would the positive impact be of cleaning this carbon off the tops of the valves & stems, if I'm understanding your pictures correctly?

If the top pics are of a 2018 model engine with only 80K miles on it, I'm wondering what an Land Cruiser 2000 engine with 180K on it would look like. Other than mileage dropping from 16+ to 13.6-14.4 mpg with 80/90 octane fuel, there doesn't seem to be any performance issues. What might I possibly expect, if anything?

Thanks.

The LC 200 is supposed to use only premium fuel. Mine runs like crap and mileage drops if I use lesser fuel.

[WoodieSC]

The LC 200 is supposed to use only premium fuel. Mine runs like crap and mileage drops if I use lesser fuel.

I should have made it more clear. Mine is a 100 series, model year 2000. Yes, I'm supposed to use 91 octane, but the price difference with the 89/90 octane fuel doesn't justify the mileage difference. I've never put any 87 octane in it, and wouldn't if I didn't have to. And I do try to use non-ethanol fuel when at all possible, which helps.

[DRDUCK]

I paid 5 dolla a gal for non-e 87 today. That sucks!