Yes. Unless you feel like dumping your intercooler every oil change?

If it is built up in your intercooler its getting to your intake, even if its just in vapor.

 

i dont think a catch can is a complete must, otherwise it would have come from the facotry that way. obviously it is better than no catch can, but i would say its up to you and if you care or not about getting a little oil in your lines.

 

Ok, there's a little bit of oil in my throttle body and it even looks like there is some burned onto the edge of the valve within it.

Here's what it looks like, do you guys think it's something to be worried about?

 

If the oil is at your TB then yes I would be worried. You might want to do a compression test just to rule out too much blow by caused by bad piston rings.

 

I did a compression check on March 18, 2009 at 123,050 miles (about 5,000 miles ago). Here are the readings, they seemed normal to me but let me know what you think.

(All readings in PSI)

First test:
Cyl 1: 170
Cyl 2: 152
Cyl 3: 150
Cyl 4: 180

After adding a few drops of oil in the spark plug hole:
Cyl 1: 191
Cyl 2: 163
Cyl 3: 180
Cyl 4: 184

To add to that, I just found some sand and a couple dead bugs along with carbon buildup on the top of my intake valves. Not sure whether or not this would be a related issue. No idea how that crap would have got in there, but it has me a little concerned.

 

compression is a bit low on cylinders #2 and #3. Those numbers are puts those cylinders down below 8.5:1.

 

What kind of problems is this likely to cause? Do you think oil is making it past the piston rings? Any idea what else it could be?

 

Most likely just blow by causing the oil to be pushed out of the crank case breather which ends up in the intake system and why you see it at the throttle body. You need to check the IC pipes/hoses just after the turbo to see how much oil is being pushed out of the crank case.

I had some rings go back on my stock motor, it was pushing so much oil out that my TB hose was sweating oil.

 

So a catch can would only treat the symptoms and not the cause of this, right? I'll probably need new piston rings?

 

Yeah rings are the only thing that are going to fix the issue.