Cleaned EGR valve, not sure if full circuit is needed. 111k miles

I cleaned the EGR valve today to gauge whether the EGR system seems bad enough to go through with a full cleaning circuit (cooler, intake, etc.). What do you guys think?

You can see that it looks caked in carbon before cleaning, but honestly after spraying it with parts cleaner and running a shop rag through it...it was clean and with very little sediment that came off (last 2 pictures). Visually it looked caked, but in reality it was just a thin layer of carbon. I think the revised welding line makes the first picture seem like it is caked on there, but that is just the welding line lightly dusted. Most of the sediment appeared around contact points of the valve/EGR system, the inside wasn't terrible.

As long as the 96% of the EGR piping is supplying flow, does the system really need to be cleaned? Maybe the cooler is clogged but based on the valve, I'm guessing it's not. What do you all think, should I clean the cooler or just let it be and maybe settle for cleaning the intake while I'm already in here?

 

I would guess 111k unless the previous owner did a replacement prior to 70k. I have no way of knowing for sure.

 

Yup, I’m doing that now. The intake on the block is crazy caked in carbon but I’m not sure what to do because I dont want to hit or spray the injectors (I bet those are covered too if the block itself is soaked in oil and carbon, but I haven’t seen this mentioned in the EGR circuit on the threads). The manifold itself I sprayed with cleaner and rinsed, I'm sure I didn't get everything on the internals but the inlets look fine.

The gasket on the manifold seems fine but so I guess I’ll just reuse it until 200k, but will replace it if I risk damaging the intake performance.

 

On the head too? I'm not sure how to get that thing clean without hitting the injector or dropping carbon into the chambers,=.

 

I'm going to do the cooler this weekend. Good call on the nylon brushes, I sprayed the intake manifold's small EGR passages out with brake cleaner too.

Based on my research I'm going to skip the oil catch can, doesn't seem like oil passing through is bad for the system as it should burn and it also requires the driver to change the can every 2k or so...not ideal if I ever sell the car.

 

I found the intake manifold removal / clean to be very straightforward. I used blue painter's tape to mark off all the detached pipes so I can easily remember what needs to be reattached. Cleaning the manifold: used brake cleaner, and old toothbrush to scrub, and a pipe brush for the small EGR ports on the manifold itself (you can also use one of those wooden kitchen skewers, a nail, or a 7/32" drill bit in these small holes). For the intake on the engine head itself I used the toothbrush soaked in brake cleaner and then used very fine sandpaper to remove the caked carbon where the gasket will sit. Replaced the intake gasket and the EGR valve gasket. Be sure to rinse out the manifold with water when you're done and let it dry in the sun.

It sounds like a lot but the intake manifold itself was actually very easy and quick. I'm going for the EGR cooler now and it's a pain.

 

I rinse it while it sits inside an oil pan, easy enough to store/dispose the liquid afterward. Used a watering can for rinsing as I don't have a hose available.

 

Well...here it is:



I'm thinking about scraping off the blue stuff (whatever that is) and grime. Does anyone know if I'll be ok on the original metal gaskets or should I buy new ones if I'm scraping away some of the surface?

 

Yeah, it’s weird how clogged it is. I’ve pretty much babied this thing since I got it and mostly done highway miles traveling in good CA weather. It must mean the previous owner dogged it.