Chevy Colorado & GMC Canyon banner
  • Hey Everyone! Enter your ride HERE to be a part of this months Ride of the Month Challenge!
1 - 20 of 30 Posts

·
Registered
Joined
·
42 Posts
Discussion Starter · #1 ·
I began started getting a random misfile and since i just hit 70k i figured I?d swap out the spark plugs, which requires pulling the intake manifold so i figured I?d look down at the valves since I was curious about the carbon build up with these DI engines. I was hoping it wouldn?t be too bad since i installed an elite catch can at approximately 30k miles. To say the least , I was disappointed of the amount that had accumulated. I?m consistent about changing my oil with Pennzoil Platinum/ using top tier fuel and I?m pretty heavy footed with the pedal. I took a couple of photos before scraping it off. i wasn?t able to get photos of the heavier build up ones towards the rear but there were some significant clusters
 

Attachments

·
Registered
Joined
·
639 Posts
Thats why i am going to do the upper cleaning maintenence program. Just before Every other oil change i will be spraying that crc intake valve cleaner through the intake. Did it on my wifes DI buick at 20k and it made a difference with performance and smoothness according to her. My truck has 17kmon it so next oilmchange i will start it. I also change the oil every 5k or year and run a bottle of techron thru it every couply of k
 

·
Registered
Joined
·
1,168 Posts
I'm just waiting for nanotechnology to come of age & for someone to release "Nano-Bot" Upper Engine Cleaner in a bottle! ;-)
.
 

·
Registered
Joined
·
1,051 Posts
Thats why i am going to do the upper cleaning maintenence program. Just before Every other oil change i will be spraying that crc intake valve cleaner through the intake. Did it on my wifes DI buick at 20k and it made a difference with performance and smoothness according to her. My truck has 17kmon it so next oilmchange i will start it. I also change the oil every 5k or year and run a bottle of techron thru it every couply of k
Being a DI engine, what do you think the Techron will do for valve coking?
 

·
Registered
Joined
·
345 Posts
That's definitely normal and well tested for. Under no circumstances would that amount of deposit even be looked at twice. Whether that disappoints you or not the truth is that is considered normal and compensated for during validation, etc.

Seeing that this is your engine and you want to take the best care of it as possible I'd recommend switch from pennzoil to mobil 1. I'd also recommend not just staying in top tier, but keep with Shell only. Shell is one of the only companies that maintain the distillation curves no matter summer/winter fuels and this aids a lot in fuel dilution and ultimate engine performance and carbon build up.

Also if you are driving a lot of short trips and intake cleaner can help, however, is not needed realistically. Winter gas contains a bit more ethanol (15% I believe is new upcoming standard if not current) and that tends to gum up the intake system. Either way those photos you provided are 100% normal, willing to bet the random misfire you claim is a different issue.
 

·
Registered
Joined
·
639 Posts
That's definitely normal and well tested for. Under no circumstances would that amount of deposit even be looked at twice. Whether that disappoints you or not the truth is that is considered normal and compensated for during validation, etc.

Seeing that this is your engine and you want to take the best care of it as possible I'd recommend switch from pennzoil to mobil 1. I'd also recommend not just staying in top tier, but keep with Shell only. Shell is one of the only companies that maintain the distillation curves no matter summer/winter fuels and this aids a lot in fuel dilution and ultimate engine performance and carbon build up.

Also if you are driving a lot of short trips and intake cleaner can help, however, is not needed realistically. Winter gas contains a bit more ethanol (15% I believe is new upcoming standard if not current) and that tends to gum up the intake system. Either way those photos you provided are 100% normal, willing to bet the random misfire you claim is a different issue.
Why Mobil 1 over Pennz platinum. I'am not on either side of that argument I switch between the 2 depending on whats on sale but if there is a difference please share.
 

·
Registered
Joined
·
407 Posts
I've seen several oil breakdown tests in other forums that show Pennzoil to be Superior to mobil 1... Also I'm afraid of what mine look like at 55k and no catch can. I'm developing a stumble at idle... Plan is to run it to 100k and then do a valve cleaning and put a catch can on it then...

Sent from my BLN-L24 using Tapatalk
 

·
Registered
Joined
·
345 Posts
It’s not about what is better on OSA’s. I’m sure they are equal when you analyze them side by side. It’s about that is what the engines were developed on and who supplies the oil for the engines. Also stumbles at idle is usually more a fuel issue than an air issue. That amount of carbon, which I’ve seems worse, won’t cause that issue. Carbon build up happens no matter what.


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
10,627 Posts
No. The cleaner must be introduced before the combustion chamber for it to work.
You are of coarse assuming it will work. I personally sincerely doubt it. Have you ever been able to spray cooked on carbon off of anything? It's just not going to happen on the back of the valves.
 

·
Registered
Joined
·
10,627 Posts
I began started getting a random misfile and since i just hit 70k i figured I?d swap out the spark plugs, which requires pulling the intake manifold so i figured I?d look down at the valves since I was curious about the carbon build up with these DI engines. I was hoping it wouldn?t be too bad since i installed an elite catch can at approximately 30k miles. To say the least , I was disappointed of the amount that had accumulated. I?m consistent about changing my oil with Pennzoil Platinum/ using top tier fuel and I?m pretty heavy footed with the pedal. I took a couple of photos before scraping it off. i wasn?t able to get photos of the heavier build up ones towards the rear but there were some significant clusters
At 30k it was way too late to install the can. Of course good for you for doing it though. I saw quite a bit of buildup on mine at 5K. Yes, no kidding, 5k. I have pics in another thread from mine when I first got my truck. You can search for it if interested. I'm hoping the can works, it sure does stop a lot of oil from going in the intake. I highly recommend one along with syn oil. Others are preaching Top tier gas. It won't help a bit for this. Injectors maybe, combustion chamber maybe, but not the back of the valves. Top Tier really turned me off when I discovered it must be at least 10% ethanol. What a joke. Must be a corn farmer thing or something.

Thanks for sharing the info!

You have to remove the intake to get to the plugs? Really? Didn't know that! Damn. What did the plugs look like?

Did the miss go away after your repairs? Did it set a code for the miss or did you just feel it?

:serious:
 

·
Registered
Joined
·
10,627 Posts
I've seen several oil breakdown tests in other forums that show Pennzoil to be Superior to mobil 1... Also I'm afraid of what mine look like at 55k and no catch can. I'm developing a stumble at idle... Plan is to run it to 100k and then do a valve cleaning and put a catch can on it then...

Sent from my BLN-L24 using Tapatalk
Why wait to do the can? You WANT to clean an extra 45K worth of crap off the valves at 100k?

Just sayin..
 

·
Premium Member
Joined
·
659 Posts
Yes, on the LFX you have to pull intake off to remove all of the plugs. Actually, you can remove 4 or 5 of the plugs without removing the intake but you need to pull it off to remove the plug under the throttle body.

It is an extra step, but not really a big deal to remove the intake. On the plus side, the gasket is reusable and you can look at the back side of intake valves.
 

·
Registered
Joined
·
10,627 Posts
That's definitely normal and well tested for. Under no circumstances would that amount of deposit even be looked at twice. Whether that disappoints you or not the truth is that is considered normal and compensated for during validation, etc.

Seeing that this is your engine and you want to take the best care of it as possible I'd recommend switch from pennzoil to mobil 1. I'd also recommend not just staying in top tier, but keep with Shell only. Shell is one of the only companies that maintain the distillation curves no matter summer/winter fuels and this aids a lot in fuel dilution and ultimate engine performance and carbon build up.

Also if you are driving a lot of short trips and intake cleaner can help, however, is not needed realistically. Winter gas contains a bit more ethanol (15% I believe is new upcoming standard if not current) and that tends to gum up the intake system. Either way those photos you provided are 100% normal, willing to bet the random misfire you claim is a different issue.
That amount of carbon on the valves is normal and will not cause any problem, shouldn't even be looked at twice? Is that what you are saying? GM redesigned the PCV system to try and slow oil going to the intake on the next production engine. You know? Seems like a lot of trouble for nothing to me. Agreed it is 100% "normal". But in this case normal isn't a good thing. No? But yes it isn't the end of the world or anything, valves can be cleaned. It is just expensive and very inconvenient to do.

Fuel has absolutely nothing to do with intake valve coking. Just sayin..

I'll agree that the miss could be something else, but I'm a little curious and concerned about what happens at high mileage on my DI engine. I have a can and I can clean the valves myself but I'd rather not have to.

I really wonder what they would have looked like at 70k with no can on it for 40k of that.
 

·
Registered
Joined
·
345 Posts
That amount of carbon on the valves is normal and will not cause any problem, shouldn't even be looked at twice? Is that what you are saying? GM redesigned the PCV system to try and slow oil going to the intake on the next production engine. You know? Seems like a lot of trouble for nothing to me. Agreed it is 100% "normal". But in this case normal isn't a good thing. No? But yes it isn't the end of the world or anything, valves can be cleaned. It is just expensive and very inconvenient to do.

Fuel has absolutely nothing to do with intake valve coking. Just sayin..

I'll agree that the miss could be something else, but I'm a little curious and concerned about what happens at high mileage on my DI engine. I have a can and I can clean the valves myself but I'd rather not have to.

I really wonder what they would have looked like at 70k with no can on it for 40k of that.
I am not saying it shouldn't be looked at twice. I'm saying that since it 'normal' it wouldn't be. Also comparing the LFX to the LGX/Z is not an equal comparison. If you have not looked in depth into the differences in the block and heads you should as they are not even close to being the same. The entire block was redesigned so of course the PCV system was redesigned.

And if you know anything about fuel dilution and how the PCV system works you would know that fuel does indeed have something do with intake valve coking. Yes coking is driven by PCV vapors, but PCV vapors are primarily fuel being recirculated into the intake system to be burnt again for efficiency purposes. So depending on the fuel you use you will see more/less carbon buildup. This extends back to my previous reference in what fuels to use and why. Ideally you would want a fuel with a good burnoff curve because you want the vapors in the intake system to clean the tracts. Lower grade/types of fuels do not achieve this.

Either way the intake valve coking isn't going to cause misfires.
 
1 - 20 of 30 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top