[shah269]

Wall nut shells that is boys and girls!
Get your wall nut shells! It’s good for what causes your intake valves from looking like fuzzy caterpillars!

So I’m looking around….almost all the new high end high HP cars are TDI engines…..and not Diesel TDI.
And we all know how well DI engines are in turning pretty little intake valves into chunky curd covered messes!
As such it’s only fair to assume that the market will be filled with wall nut snacks and the price of wall nut shells will be par with Google stock!

Has any auto company given a thought as to how to fix this mess?
My friend who works in Volvo isn't saying a word!

So that means.....they sell you the car...and it's your job to nut blast your car every 40k miles

[KingOfJericho]

"Walnut" is the word you're looking for...

I got a letter from Audi a few weeks ago saying that carbon cleaning is now covered by warranty up to 120,000 miles. I had my 135i walnut blasted at roughly 18k under warranty as well.

[shah269]

No no no...Walnuts are free and grow on trees!
Wall nut is what you feel when you have to pay to have your vavles blasted every 20k miles. We will call them "Wall Nut" (tm)
I have 49k miles.....on my CPO and I don't think it's covered.
but it looks as if all the other new turbo TDI cars will have this issue.....

[KingOfJericho]

Did you even ask the dealer?

[Sedoy]

Some companies already trying to address this issue:
Toyota/Audi - using both direct and port injection (for example new Audi EA888). Also, Toyota hasn’t announced their DI Turbo yet, probobly because of this issue.
Mazda – claims that keeping intake valve temperatures above 400C will prevent deposits on their non-turbo DI.

Personally, I would stay away from DI engines for the next few years until this issue is resolved.

[shah269]

Originally Posted by KingOfJericho

Did you even ask the dealer?

Yeah when i was in for a valve cover leak i brought it up....they said they were going to look into it. I'm still waiting to see what they say.

The oddest thing regarding DI is what my friend from Volvo told me in passing "If you have a stick you should be fine due to engine braking on the high way"

I’m a mech E and when he told me that…my head hurt? How the hell does engine braking help prevent carbon buildup?
The only thing I could think of was that maybe doing so caused the valves to heat up to a point where the “gunk” holding the carbon on dried off?

But he wouldn’t tell me so….i stopped asking.

Makes you wonder what Cadillac / GM is going to do? Could you imagine all those Cadillac’s with the V6 TDI engines conking out at 45k miles due to carbon build up?

[KingOfJericho]

45k? My 135i was stuttering like crazy by 15k. The S4 was cleaned by the dealer as a part of the certification process at 31k. Both are manual transmission.

[Sedoy]

Guys stop calling it "TDI" call it... FIDI

[shah269]

FDI
Forced Direct Injection.
What's with the first I?

[KingOfJericho]

Forced Induction Direct Injection.

[Sedoy]

yep

Originally Posted by KingOfJericho

Forced Induction Direct Injection.

[shah269]

Fidi sounds like one pissed off cat.....

[Red Bread]

Let's not go claiming it's only turbo charged DI cars that have this issue. The B7 RS4 is the first major case of carbon build up in DI engines. The Toyobaru is DI with port injection that's supposed to wash the intake valves, but that motor has had some cases of fuel starvation, so not all is right with that setup yet either. It will be interesting to see how the newer Audi engines do with their dual injection setup.

[KingOfJericho]

Originally Posted by shah269

Fidi sounds like one pissed off cat.....

or this fellow:

[shah269]

fuel starvation? how the hell do you have that when you hav DI and port injection?

[Red Bread]

Originally Posted by shah269

fuel starvation? how the hell do you have that when you hav DI and port injection?

It appears to be heat related. The rental fleet of Nurburgring BRZ's was pulled because of it and a small number of customer cars have also had reported issues. From what I understand of this particular system, the port injectors are not powerful enough to provide a fall back when/if the DI system fails, so in that way, you're not much better off than the HPFP failures BMW had.

[shah269]

So you get carbon build up and y our main DI sysem goes down! Major win Toyota!

[Red Bread]

Originally Posted by shah269

So you get carbon build up and y our main DI sysem goes down! Major win Toyota!

Haha, technically, the port injection should keep the carbon buildup down, but you still get HPFP failures, so you just have a clean, dead motor instead of a dirty dead motor.

[shah269]

Clean and dead or dirty and dead?
Ever have the funny feeling that all of this would be a non issue if they gathered all the accountants in the engineering department and threw them out of a window from the top floor?
Boys and i'm sure there is at least one girl engineer....Teflon! Take valves....cover in Teflon...solve problem….high five each other…go and look out of the window of the carnage of accountants in the parking lot.

[shah269]

ok guys...long day lots of meetings....quick google....why isn't any one Teflon coating their intakes?