Why DIrect Injection is really bad!

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When I was doing my intake manifold cleaning, I was shell-shocked by how much oil and [censored] was in the intake tracts. I'm hoping this can help future DI engine owners understand what they are facing.

I was also super-happy that my intake valves were ok because thankfully Honda back then wasn't stupid and hadn't fallen for the false promises and company greed that comes from using a single set of Direct Injectors.

FYI, if you own a Toyota with D4-S or are a lucky owner of an Audi with the 2.0T in Eastern Europe - you guys all have a set of port injectors in order to meet and beat the emissions regulations that don't allow the type of particulate emissions that DI is responsible for. Smart choice!

Pics --

The seal that faces the top of the intake manifold


Intake Manifold cover. The dark crusty stuff is the soot marking the EGR system.



Intake Manifold plenum center part. By design it catches the majority of the oil coming in from PCV system. This is 202.5k mi. of collection. It took 4 hours with Throttle body cleaner and a toothbrush to take the heat-caked oil off.


The following are each of the 6 cylinder intake ports on the engine. Just think what my intake valves would look like if the injector wasn't there to keep them clean. Based on this, I can say there's absolutely no way in [censored] a DI engine can survive for long without a 100.00% removal of all contaminants from intake air (FYI, this is impossible as of right now in production cars. An OCC is a must-have if you plan on buying a DI car.)





 
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Uh..there are no false promises around Direct Injection. It offers superior engine performance vs port injection. Common rail diesel tech is the most obvious example.

Sure some engines have "some" build up and some early models had significant amount of it but overall it's not a big deal.
 
Originally Posted By: Kamele0N
So Audi is assembling different 2.0 TFSi engines for the West and East europe?

Not sure if it's an east vs west thing, but it is true that VAG is using different versions of their engines equipped with secondary port fuel injectors in order to meet emissions requirements in some countries. USA isn't one of those countries.

A side benefit of having this secondary injector is that it helps wash off the valves.
 
Heck, I've decided I don't even want ODBII... So all my stuff will be pre-1995 from now on
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As some of you know, I just got a super clean 1993 F-150 extended cab 4x4 with only 83K
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I'll just keep looking for other early garage queens
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So I didn't read it in the original post, but someone mentioned 202K ... I'd say that engine looks fine for 202K
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Sure a little clean-up will be nice, but I don't see any restricted air flow of anything
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However, I get your point and I'm not a fan of DI. I'll stay with port injection for the foreseeable future
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202k and you're [censored] and moaning about it? Really? Seriously? It's really nothing to worry about and probably would go another 202k wothout issue.


I also call [censored] on the rest of the "you need an intake cleaning on all DI cars" nonsense. Early VW, Audi, BMW, yes. But the rest of the world has figured it out and it's not an issue. Heck, Ford probably has the most DI cars on the road and you don't hear of them really being issues. And yes those engines are getting the miles on them now (been around since late 2009).
 
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Originally Posted By: KL31
What's this have to do with DI? Port injection looks like this after that many miles too.


Exactly. My Chevy 5.7 Vortec looks like this too.
 
Ummmmm..... that doesnt look too bad...

This looks like a Honda J series. All but the very newest Honda Js are "regular" fuel injection. So im 95% sure this is NOT a picure of a DI issue.

What kind of car is this?
 
Maybe I'm missing something here, but regardless of how the fuel is injected you are pretty much always going to have oily junk build-up in the nooks and crannies of the upper intake due to the PCV system and EGR system if so equipped with EGR. It rarely hurts anything.
 
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Originally Posted By: rotorcraft230
Looks like to me that 4 ports are cracked between the valves on the head.
Agreed; those are not casting lines. Not sure what it means for that engine, but it is particularly obvious on this photo:


 
Originally Posted By: 2015_PSD
Originally Posted By: rotorcraft230
Looks like to me that 4 ports are cracked between the valves on the head.
Agreed; those are not casting lines. Not sure what it means for that engine, but it is particularly obvious on this photo:






Interesting, I'd love to see that.
 
Include the history of this engine, otherwise this post is worthless. Did it get junk oil? Race engine? Aftermarket tune? I'm not sure why this is an issue after 200,000 miles...even a well cared for engine.
 
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