Direct Injection Intake Deposits
Thread Starter
Instructor
Joined: Jul 2017
Posts: 127
Likes: 32
From: Shelby Twp Michigan
Direct Injection Intake Deposits
At the risk of beating a dead horse, it is 4 years since the introduction of the C7. There must be some high mileage 2014 models out there. Have those of you who are in that group experienced any noticeable reduction in engine performance or malfunctions?
Le Mans Master
Joined: Dec 2000
Posts: 9,899
Likes: 1,839
From: Hot Springs AR
I just got my '14 last March, 91K miles on her to date (8K of those are mine). I can't tell you about any degradation in performance, but I'm going to do a cleaning in the "hopefully" near future, and I'm going to document what I find.
Not exactly what you wanted, but hopefully it'll help.
BTW, she still launches like a cat that just had its tail stepped on.
Have a good one,
Mike
Not exactly what you wanted, but hopefully it'll help.
BTW, she still launches like a cat that just had its tail stepped on.
Have a good one,
Mike
Le Mans Master
Joined: Aug 2000
Posts: 6,486
Likes: 1,659
From: Las Vegas NV
Please do keep us informed, VetteDrmr.
Would love to see some *1st hand* experience with this on an actual C7, and yours certainly has the miles that would exhibit the problem if it exists.
Would love to see some *1st hand* experience with this on an actual C7, and yours certainly has the miles that would exhibit the problem if it exists.
Le Mans Master
Joined: Dec 2000
Posts: 9,899
Likes: 1,839
From: Hot Springs AR
Have a good one,
Mike
Burning Brakes
Joined: Apr 2014
Posts: 780
Likes: 176
From: MV CA
Interested in this thread cause I have a 2014 since 3-27-2014 brand new and as a daily driver I have 15, 453 miles on it. Just last March 2017 i threw on A&A SC with meth and it is fast. it was fast before but with SC it is faster. Now that I am subscribed I will get to see what the rest of your experiences are with the valve cocking or not?
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,101
From: Fulshear, TX
For your first time doing it, plan on 2 hours to R&R the intake manifold. The more you do it, the quicker you'll get at it. I've swapped on various ported intake manifolds and show zero signs of oil coking on the valves.
Safety Car
Joined: Aug 2012
Posts: 3,960
Likes: 1,106
I don't have that many miles on my 2016 Z06 but my first gas DI vehicles was a 2008 Cadillac CTS with the 3.6L DI and when I traded it in at 80K the highway and overall mileage was the same as it was when I brought it home new and there was no noticeable change in power.
Some DI engines, like some of the early BMW efforts, were very poorly designed and had major coking issues but I haven't run into that with any of my GM gas DI engines (2008 CTS, 2014 ATS, 2016 Z06).
Some DI engines, like some of the early BMW efforts, were very poorly designed and had major coking issues but I haven't run into that with any of my GM gas DI engines (2008 CTS, 2014 ATS, 2016 Z06).
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Burning Brakes
Joined: Apr 2014
Posts: 780
Likes: 176
From: MV CA
I don't have that many miles on my 2016 Z06 but my first gas DI vehicles was a 2008 Cadillac CTS with the 3.6L DI and when I traded it in at 80K the highway and overall mileage was the same as it was when I brought it home new and there was no noticeable change in power.
Some DI engines, like some of the early BMW efforts, were very poorly designed and had major coking issues but I haven't run into that with any of my GM gas DI engines (2008 CTS, 2014 ATS, 2016 Z06).
Some DI engines, like some of the early BMW efforts, were very poorly designed and had major coking issues but I haven't run into that with any of my GM gas DI engines (2008 CTS, 2014 ATS, 2016 Z06).
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,101
From: Fulshear, TX
In all my experience in modding cars, hosting dyno time, etc. over the past two decades I've seen catch-cans do more harm than good. Not necessarily because catch-cans are bad, but because the majority aren't installed and/or setup properly. In a few instances, I've actually seen them lead to blow-by and oil consumption in an otherwise fine engine.
Last edited by Kracka; Aug 11, 2017 at 09:17 AM.
Pro
Joined: Aug 2001
Posts: 626
Likes: 8
From: You talkin' to me?
I don't have that many miles on my 2016 Z06 but my first gas DI vehicles was a 2008 Cadillac CTS with the 3.6L DI and when I traded it in at 80K the highway and overall mileage was the same as it was when I brought it home new and there was no noticeable change in power.
Some DI engines, like some of the early BMW efforts, were very poorly designed and had major coking issues but I haven't run into that with any of my GM gas DI engines (2008 CTS, 2014 ATS, 2016 Z06).
Some DI engines, like some of the early BMW efforts, were very poorly designed and had major coking issues but I haven't run into that with any of my GM gas DI engines (2008 CTS, 2014 ATS, 2016 Z06).
I will say that you can certainly feel the difference when the valves are coked up.
Murnutz
Safety Car
Joined: Aug 2012
Posts: 3,960
Likes: 1,106
I have 2010 Mini Cooper S and had to have it walnut blasted last year. It only had about 45k miles on it it idled and ran rough. After getting it cleaned up it was like having a new car. Minis are pretty well known for having coking and high oil consumption issues.
I will say that you can certainly feel the difference when the valves are coked up.
Murnutz
I will say that you can certainly feel the difference when the valves are coked up.
Murnutz
All DI engines will get some "cosmetic" coking with age but in some designs the problem is far more than cosmetic.
For those who didn't see the earlier Ask Tadge question about valve coking it is here: https://www.corvetteforum.com/forums...on-valves.html
That is a great looking dog in your avatar!
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
Tech Contributor
Joined: Oct 1999
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From: Charlotte, NC (formerly Endicott, NY)
I don't have that many miles on my 2016 Z06 but my first gas DI vehicles was a 2008 Cadillac CTS with the 3.6L DI and when I traded it in at 80K the highway and overall mileage was the same as it was when I brought it home new and there was no noticeable change in power.
Some DI engines, like some of the early BMW efforts, were very poorly designed and had major coking issues but I haven't run into that with any of my GM gas DI engines (2008 CTS, 2014 ATS, 2016 Z06).
Some DI engines, like some of the early BMW efforts, were very poorly designed and had major coking issues but I haven't run into that with any of my GM gas DI engines (2008 CTS, 2014 ATS, 2016 Z06).
Bill