Carbon and a direct Injection

[fishingstar]

I have a 14 Impala with 3.6 in it that has 66000on it. I started getting a p0301 code.

Took it in to the dealer they found low compression. They told me that they are having problems

with the dI engines building up carbon on the valves. So they are going to do a valve job on the heads.

They said it has to do with oil quality I reminded  them that they did all oil changes up to the warranty at 48000

at that point I started to do them my self and used mobile 1. So I'm not buying it.

Do anybody heard of this and how do I stop it from happening again.

 

At this rate this car will be off warranty in less then a year.  

[ESSGuy]

I don't know about the car, but I have a 15 Silverado 6.2 and I put on an oil catch can, its made by Elite engineering. I get roughly 2-4 oz every 1000 miles in the can that otherwise would have been on the valves. Check it out and see if they make one for the cars, I know they do for the camaro and corvette.

[fishingstar]

thanks for the help. this is all new to me I will check into it.

[Mike89]

maybe I'm missing something but could the fuel one uses be a part of this problem?

[fishingstar]

From what I under stand the injector is in the combustion chamber the gas does not wash over the valve when the gas is injected. So all of the byproducts stick to the hot valve. 

indirect injection will inject gas so it will wash the deposits off the intake valves.

So long story short gas should have no impact on it.

This is all new to me and I'm trying to understand it and prevent it from happening again.

So if i'm wrong on any thing set me straight.

 

[ESSGuy]

You are correct in that a direct injection motor the gas does not wash over the valves. On my Silverado the pcv hose comes from the crankcase and runs back to the intake which runs the dirty oil vapors onto the intake valves, now with my oil catch can it runs from crankcase to catch can, which separates oil from the air before running back into the intake. The new ford ecoboost motor for 2017 has both port and direct injection to help alleviate crusted up valves.

[Jeremy airjer W]

Most if not all the manufacturers are running into this issue with direct injection. Upper intake cleanings an a regular basis may be another option to consider.

 

The good news is the timing chain will stretch and cause all kinds of problems. You will most likely be out of warranty when this happens. 

[delcecchi]

Makes a guy glad their tax dollars were used to bail out GM, eh?

[Mike89]

chevy trucks have this too?  it's a 2011  5.3

[ESSGuy]

Chevy started in 2014 with DI. Before then your fine, port injection.

[fishingstar]

looks like I have to put up with it on my new pickup

 

[Mike89]

thanks

[fishingstar]

Got my car back yesterday. They cleaned up the head found a bad injector then found a small vacuum leak. After 80 some miles got the same 301 code. They are telling me that the extra fuel from the bad injector was causing the extra carbon buildup. That all makes sense but obviously they have not found all the problems. 

[leech~~]

37 minutes ago, fishingstar said:

Got my car back yesterday. They cleaned up the head found a bad injector then found a small vacuum leak. After 80 some miles got the same 301 code. They are telling me that the extra fuel from the bad injector was causing the extra carbon buildup. That all makes sense but obviously they have not found all the problems. 

 

Did they throw on a new wire and plug on C1?

[Jeremy airjer W]

7 hours ago, leech~~ said:

 

Did they throw on a new wire and plug on C1?

coil over plug. no wire.

 

I just did an injector on a 3.6. Not a real fun job. The injector stuck open and filled the cylinder with fuel. After replacing the injector the engine ran but soon developed some undesirable noises. It is getting a new motor on thursday...

[leech~~]

58 minutes ago, Jeremy airjer W said:

coil over plug. no wire.

 

I just did an injector on a 3.6. Not a real fun job. The injector stuck open and filled the cylinder with fuel. After replacing the injector the engine ran but soon developed some undesirable noises. It is getting a new motor on thursday...

 

Doesn't like to run with a crank full of gas huh! Lol

 

[fishingstar]

from what they told me the oil had some gas in it. 

before they took the car I looked at the dipstick and it didn't look high.

[Jeremy airjer W]

On 12/13/2016 at 5:42 PM, leech~~ said:

 

Doesn't like to run with a crank full of gas huh! Lol

 

The oil was changed with the injector replacement, It definitely smelled like gas....