Do injectors in DI engines ever get dirty?

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I've been trying to find definitive information on whether the injectors themselves in direct injected engines ever get dirty to the point where the fuel may not be injected as a perfectly fine mist into the cylinder. I've found some that say that fuel pressure is so high in DI engines that contaminants are unable to build up on the injector tip. Is this the general consensus for all DI systems?

If the injectors have been known to get dirty, do fuel additives help?
 
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Modern diesels run very high fuel pressures and can still get deposits on the tips. Using low quality gas I'm sure could cause problems in direct injection systems.
 
You bring up a good question. I've got 150k on my CTS 3.6DI and all seems well. I toss in a bottle of Techron or Gumout PEA cleaner every oil change or so just as matter of course.
 
I've seen no evidence that additional fuel injector additives are needed if you use top tier fuel regularly. My wife and I only buy top tier (mostly Chevron) and have not suffered any drivability issues in out direct injection engines over the years.

Perhaps if non top tier fuel or old gas is used, then using additional additives may be necessary.
 
If i'm ever going on a long road trip i'll throw a bottle of GUMOUT in the tank.
 
The book for my 11 Sonata says to use Chevron Techron every 3k miles.

I have never seen an OEM recommend fuel additive, but I have been buying injector cleaner of various brands every 3750.
 
Originally Posted By: BikeWhisperer
I've seen no evidence that additional fuel injector additives are needed if you use top tier fuel regularly. My wife and I only buy top tier (mostly Chevron) and have not suffered any drivability issues in out direct injection engines over the years.

Perhaps if non top tier fuel or old gas is used, then using additional additives may be necessary.


Knock on wood I have noticed this as well. I only use Shell V-Power in my Mustang and my mom only uses Shell and sometimes V-Power in her EB Fusion and we have not had any issues that I see other cars having with random misfires.
 
Originally Posted By: rooflessVW
DI injectors can and do get clogged. This is why OEMs recommend "top tier fuel."


I'd not be so quick on that - I just checked and Ford, the manufacturer with probably the most DI engines on the road (all EB's are DI) doesn't mention Top Tier Fuel in the owner's manual....

I know I use the cheapest swill in my 2 EB's and at 122k and 84k no hint of injector issues.
 
I had to replace the intake manifold on my VW at 80 or 82K miles, I cant remember. The car ran perfectly fine before the intake secondaries quit opening, letting more airflow through for high RPM driving conditions. The intake valves and fuel injectors were very dirty. I cleaned everything up before putting the intake back on. The car didn't run any better other than the secondaries were functioning.

Pic of one of my injectors:


 
I can only speak for Hyundai’s here but they do have a valve that needs spraying supposedly around 50 K miles . You just push aside the rubber on the intake slip the straw in and spray while it’s running. It’s some sort of power valve that you can’t get at. That getting crusty as they can do will seriously inhibit your acceleration. You get the stuff even at Wallymart by the spray oils
I can’t say all DI engines have them . I do know the infamous Hyundai Theta series engines has this supposed need.
 
They sure do, I do them all the time. PEA cleaners help but I notice something else happening to them when they get higher miles on them.
The filters are burned out leaving only the metal ring and no filter. I found this on a few Mazda and VW/Audi injectors, the injectors were partially clogged with burned plastic filter material so no amount of cleaner is fixing that.
The good thing is that cleaning them and reverse flushing them cleans it out successfully.
 
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