Will EGR pipe inspection help me determine how bad EGR is?

If you have liquid resting on the discharge side of the check valve (in this case the PCV), you’ll have to overcome the liquid force along with the spring set pressure prior to the valve performing its designed function .

While that may seem trivial, over time you’ll give the spring a new “memory” of how to work, which will affect long term functionality .

So if you put the “wide spot in the line” below the PCV valve, it can free drain and not affect it.

Hope that helps.

 

For me it was a slam dunk to locate the OCC low: lotsa room, short hose runs, cross beam convenient for mounting, and any caught oil/water needs to climb to escape the can.

 

Sorry, I tried to be as layman as I could.

 

This statement is plausible from my engine component tear down at 120 K miles. Upon inspection of the IM, throttle body, EGR pipe, and spark plugs (haven't taken apart the EGR assembly yet), found them to be very clean with little soot. I do mostly highway driving causing the engine to run constantly at low RPM most of the time.

 

Hmm so do we have consensus where the best OCC mount point is? Over on the OCC thread the OP had 3D printed a mounting plate that at least some have used. However, the mount point in that thread would be higher than the PCV valve. Also, does a low mount point have sufficient access to easily check the OCC level...etc?

I think I'm going to hold off on OCC install for now (and just do the manifold cleaning) until we get a little more 'data' on how the OCCs are doing.

 

Access from above for mine is definitely awkward. It works for me though, since the OCC I'm using has a tap on the underside, and I'm under the car with the engine underpanel off, every 6 months for an oil change, and we're quite low mileage.

When I checked mine, about 2380 kms post install (at end of December) I got around 50 cc. I'd suspect that time of year is worst case, it'd be lesser amounts through summer. I'd guesstimate the working capacity of mine (Moroso 85474 Universal Air/Oil Separator) is about a cup.

 

Ah a request for data.

I have some, but it is from the Northern California climate where it hasn’t dropped below freezing, so take this with a grain of salt.

I have ours mounted to the lower cross member and check the oil catch can dip stick every weekend, which is every 400-500 miles. I have put 6 k on our 2010 since the install and have accumulated about 1/8 of an inch of “material”.

When I do the preventative maintenance in a couple of weeks I’ll dump the oil catch can and measure the amount.

More to come.

 

As promised, I found a couple of sources.

Page 7, figures 10a and 10c in this research paper depict for a gasoline engine the huge spike (10x) in particulates during acceleration and cold starting. The largest increases happen when their test vehicle accelerates from 80 km/h to 100 km/h and also from 100 km/h to 120 km/h.

Also from this paper:

"Finally, although the engine braking increases the total particle number emission of the studied vehicle, it should be noted that the total emission was dominated by particles emitted during acceleration conditions."

An electric motor assisting acceleration of the vehicle can mitigate some of the soot production that occurs from extra fuel and/or EGR during acceleration. May be a good reason to pick a Prius Prime or future hybrid with a more powerful electric motor & battery.

 

Maybe 4th gen with EGR intake downstream of the Catalytic Converter does a wholesale reduction of the clogging. Time will tell. I haven't heard of any 4th gen'rs installing an Oil Catch Can. The lazy, complacent sloths.

 

You are 'lucky' though...2nd gen Prii don't have these EGR components! Lucky you..eh?

 

They have shim style valve adjustment, bladder gas tank, coolant thermos, keeps 'em busy.