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I read the drive e engine has direct injection. I drive alot of short trips and wondered if i have carbon build up on my valves either now or later on?
I read that port injection engines spray gas into the valve area keeping the valves clean but direction injection doesnt so they get carbon build up as the car gets older and it can be a problem
 

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Make sure you run a "Top Tier" fuel. These have added detergents which will keep things clean.
 

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Is the I-6 direct injected or just the new 4 cylinders?
 

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Not sure how badly the issue manifests itself in Drive-E engines (or any direct injection engine for that matter) but that is one of the theoretical downsides of direct injection.

Under the right load conditions, every time the intake valves initially open, reversion occurs. The cylinder pressure at the end of the exhaust stroke is still higher than the intake manifold pressure and the remaining exhaust gasses temporarily flow up past the intake valve and into the inlet port. As the piston travels down it draws the exhaust gas and new intake charge back into the cylinder. This exhaust gas reversion is how the carbon deposits get onto the back side of the intake valves in the first place. Without port injectors spraying the backside of your intake valves I do not think the fuel detergents are going to do anything to help the matter.
 

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Not sure how badly the issue manifests itself in Drive-E engines (or any direct injection engine for that matter) but that is one of the theoretical downsides of direct injection.
I'm curious how badly this issue is with the Drive-e engines as well. I know first hand it was bad with VW 2.0 engine and the Lexus 2.5 V6, both of which I've owned and both of which needed expensive valve cleanings due to misfires at around 50k miles. Fortunately both were still under factory warranty at the time and both were sold before it was needed again.

The I-5 is port injected as well, one of the main reasons I bought the Volvo.
 

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My previous RenaultSport had this issue and they added the clean to the 30,000km service for $200Aud.

Ive wondered if it should be considered for this car as well

Sent from my SM-T713 using Tapatalk
 

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The main reason for dirty valves is the EGR. it is always open at low speeds and short distances. So yes, it is a problem for this engines when you often drive only short distances at low speeds. Traffic jam is also terrible.
 

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Yes, this problem raised its ugly head when direct injected engines hit the market. However, that was more than ten years ago, and I get the unscientific impression that the manufacturers have mitigated the problem over the years. The carbon deposit is comprised of oil that leaks down past the valve seals, oil and fuel that is briefly pushed up and out of the combustion chamber, and oil that is carried into the intake system via the breather system. We don't have EGR.

Problems like this are hugely expensive for the manufacturers, and they are highly motivated to resolve it. I can imagine that they took a hard look at those sources of oil and dried them up to the extent possible. I've read here about how Volvo uses the evaporative emissions cannister purge to do some cleaning. Others, like Ford, have gone so far as to add auxiliary port-mounted fuel injectors so that the engine is not always in pure direct-injection mode.

But, if it does happen, it's fixable. Not cheap if you are out of warranty, but effective. I had it done to my GTI at around 100k miles (was throwing misfire codes). Covered under warranty. The car has 180k on it now and the problem has not returned. Other than the absence of misfire codes, I did not notice any before/after differences in performance, fuel economy, startability, etc.
 
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