Solutions for DI Engines?

[Scum_Frog]

Originally Posted By: johnachak
I cant take this di stuff anymore ... since 2008, there had to be Millions of D.I. engines sold... i don't see that many posts of blown engines. I see hundreds by people worried about them. But very few of real problems with them.


+1

 

[badtlc]

Won't something like BG or Seafoam through a booster line on the intake get rid of the valve deposits if they form? If so, a $7 treatment every 20-30,000 miles seems very reasonable.

 

[SteveSRT8]

It will get rid of deposits where it TOUCHES them.

"Dry" intake manifolds are notorious for bad distribution of liquids. Expect very uneven coverage from cylinder to cylinder, and thus spotty results.

 

[Finklejag]

Originally Posted By: johnachak

I cant take this di stuff anymore ... since 2008, there had to be Millions of D.I. engines sold... i don't see that many posts of blown engines. I see hundreds by people worried about them. But very few of real problems with them.



You aren't going to see blown engines from intake deposits. What you will see is loss of power and MPG. Will the average Joe that buys a 3.6L Cadillac CTS notice this? Probably not. But a enthusiast that buys a VW GTI like myself will.

 

[RF Overlord]

Originally Posted By: wallyuwl

Haider, GM's V6 assistant chief engineer, explained how GM has designed its DI engines to combat carbon buildup: "Our intake-cam timing, injector targeting and timing of the injection events are optimized to avoid direct fuel contact on the intake valves. This strategy keeps smoke and soot formation to an absolute minimum, which in turn prevents excessive deposit formation."
I'm confused now...he's saying that avoiding direct fuel contact on the intake valves prevents excessive deposit formation. I thought it exactly the opposite: that not having direct fuel contact wasn't enabling the detergents in the fuel to clean those deposits which I also thought were caused by PCV gasses from fuel dilution of the oil and from using oils with high NOACK numbers???

 

[demarpaint]

Originally Posted By: A_Harman
That could be because Audi and Toyota had intake valve carboning issues with their early GDI engines, and it has sensitized the automotive community to the issue. Now all GDI engines are suspect. Engineers are probably writing articles to comfort owners because they also read blogs like this one and feel the need to make their case against criticism that is based on rumor and innuendo.


While that might be so and is a good point, GM clearly has fuel dilution issues. A reprogram of the OLM isn't fixing the problem it is masking it. Based on speaking with GM techs, and a few mechanics I know that worked on them the intake valve deposits are real too. But maybe the average car owner won't complain, and someone like myself will pickup on the loss of pep and idle quality.

 

[wallyuwl]

Originally Posted By: SteveSRT8
It will get rid of deposits where it TOUCHES them.

"Dry" intake manifolds are notorious for bad distribution of liquids. Expect very uneven coverage from cylinder to cylinder, and thus spotty results.


What about something like Mopar's Combustion Chamber Cleaner, which is a foam? That seemingly would solve this issue.

 

[PontiacFan]

Originally Posted By: demarpaint
I mentioned an MMO Inverse Oiler a while back. I think it would help.


Not many members listened to demarpaint back in 2005 about MMO, maybe we should be listening to him now. JMO

 

[MarkM66]

Just run a wet shot through it every once in a while.

 

[Bill in Utah]

Originally Posted By: RF Overlord
Originally Posted By: wallyuwl

Haider, GM's V6 assistant chief engineer, explained how GM has designed its DI engines to combat carbon buildup: "Our intake-cam timing, injector targeting and timing of the injection events are optimized to avoid direct fuel contact on the intake valves. This strategy keeps smoke and soot formation to an absolute minimum, which in turn prevents excessive deposit formation."
I'm confused now...he's saying that avoiding direct fuel contact on the intake valves prevents excessive deposit formation. I thought it exactly the opposite: that not having direct fuel contact wasn't enabling the detergents in the fuel to clean those deposits which I also thought were caused by PCV gasses from fuel dilution of the oil and from using oils with high NOACK numbers???


Maybe that is why he is an "assistant" chief engineer.

The issue IS that fuel is NOT washing the intake valves (like normal motors) so the deposits ARE staying on the intake system BEFORE the combustion chamber (and fuel injectors). He can do all they want with timing, fuel and such but if the problem is BEFORE the fuel nothing they do will effect this issue IMO.

I think they are just dropping marketing driven quotes to keep the masses at bay. If someone trades in their vehicle often enough (which they WANT you to do) then no problem. The person who keeps their vehicles deposit cleaning is "normal" maintenance which they love to charge for.

I mean its only a "couple of bucks" here and there so no big deal when compared to this or that.

It's those "couple of bucks" here and there that is killing this country.

 

[badtlc]

Originally Posted By: SteveSRT8
It will get rid of deposits where it TOUCHES them.

"Dry" intake manifolds are notorious for bad distribution of liquids. Expect very uneven coverage from cylinder to cylinder, and thus spotty results.


OK, so Amsoil power foam then. Still pretty cheap.

 

[demarpaint]

MMO via an Inverse Oiler early in the life of the engine is my bet. It might keep the deposits at bay, fuel dilution is an entirely different problem. IIRC there was some discussion on the MMO board about the intake valve deposits.

 

[johnachak]

Originally Posted By: Finklejag

I cant take this di stuff anymore ... since 2008, there had to be Millions of D.I. engines sold... i don't see that many posts of blown engines.


You aren't going to see blown engines from intake deposits. What you will see is loss of power and MPG. Will the average Joe that buys a 3.6L Cadillac CTS notice this? Probably not. But a enthusiast that buys a VW GTI like myself will.


Wait a minute. I bought a custom spec'ed $50000 sport sedan with 304 hp; sport suspension, big brakes and wheels YOU are the enthusiast with a bug on steroids? Get serious!

 

[Bill in Utah]

Originally Posted By: johnachak
Originally Posted By: Finklejag

I cant take this di stuff anymore ... since 2008, there had to be Millions of D.I. engines sold... i don't see that many posts of blown engines.


You aren't going to see blown engines from intake deposits. What you will see is loss of power and MPG. Will the average Joe that buys a 3.6L Cadillac CTS notice this? Probably not. But a enthusiast that buys a VW GTI like myself will.


Wait a minute. I bought a custom spec'ed $50000 sport sedan with 304 hp; sport suspension, big brakes and wheels YOU are the enthusiast with a bug on steroids? Get serious!


I'd suggest (strongly) that you respect what others drive and stop with the insults.

Bill

 

[johnachak]

You aren't going to see blown engines from intake deposits. What you will see is loss of power and MPG. Will the average Joe that buys a 3.6L Cadillac CTS notice this? Probably not. But a enthusiast that buys a VW GTI like myself will. [/quote]

This Caddy is by far the best STOCK car I have ever driven. I spec'ed it myself. I have driven many cars in my time including a VW GTI.. fun little car yes, in my opinion it doesn't even come close to this car and it is a luxury vehicle to boot. It not only is sick fast but the handling with the sport suspension and awd is phenomenal.

 

[demarpaint]

^^How many miles on the Caddy?^^ Do you have any UOA reports to post? Just wondering that's all.

 

[johnachak]

Originally Posted By: demarpaint
^^How many miles on the Caddy?^^ Do you have any UOA reports to post? Just wondering that's all.


Sorry to disappoint, no UOA. but this is my baby. She's garaged, only has 16,000 miles and I use Mobil 1 5w 30 and change it every 6 months. Thats thats around 3000 or so OCI. (Built in June 08) Overkill, but so what. I never saw a need to do a UOA on Mobil 1 <3000 miles. If she ever seems to slow down, Caddy offers an intake cleaning Service... About $250 I think. While its under the 100000 mile warranty I guess I'll have to use them to be on the safe side for that... I do the rest of the maintenance. I already have the GM fluids for the rear & front differentials and the transfer case. Waiting for 20000 to do those. I want to get the ff out but I am trying not to be too over the top.

 

[MuzzleFlash40]

I really don't think he wan insulting your car, he was just speaking in general. He could have picked any sedan for his statement, he just chose to use the cts. Don't take it personally.

 

[demarpaint]

Originally Posted By: johnachak
Originally Posted By: demarpaint
^^How many miles on the Caddy?^^ Do you have any UOA reports to post? Just wondering that's all.


Sorry to disappoint, no UOA. but this is my baby. She's garaged, only has 16,000 miles and I use Mobil 1 5w 30 and change it every 6 months. Thats thats around 3000 or so OCI. (Built in June 08) Overkill, but so what. I never saw a need to do a UOA on Mobil 1 div>


Sounds like a solid plan to me. When you spend $50K on a car, and read threads like these being on the safe side IMO is the smart thing to do! I would suggest a UOA when you get to 20K miles to make sure there are no fuel dilution issues! Enjoy the car!

 

[johnachak]

Ok, gotcha' I guess he never heard of a sports sedan...
This is the car of a lifetime to me. I have had Impala Ss (66), camaro, El Camino, worked many engines with friends, driven Cudas, firebirds, sleeper novas, a sleeper coronet 440, etc. My brother is a foreign car nut so he had me drive everything from a celica gt to a vw gti. Lets not forget the Hondas... I loved fixing them for him all the time.

I guess I got carried away.. sorry if I offended anyone. If I hit the lotto and get my CTS V I really wont want to hear it ...