AUA Oil Separator - clean or just refit?

[ajsellors]

In the course of trying to get to the bottom of my Long Term Fuel Trim Additive Air System too Lean error I have just removed the oil separator and attached hose that's behind the engine for inspection.

Although the hose shows signs of rubbing in two places, it and the oil separator box look sound. The hose however didn't have a retaining clip on the manifold end. It just pulled off, easily!

I was prepared for a view of mayonnaise horror but it all looks OK. I can easily blow air though the hose and out of each opening on the separator so it doesn't look like it is blocked with anything.

Is it worth cleaning or should I just refit, with a clip!

Is air meant to just be able to flow through or should there be some kind of valve inside?

Any advice would be appreciated.

regards

Andrew

 

[Olerype]

Have the same error. How was access to the separator and removal - easy?

As Jannes pointed out here in this forum, the System too lean is maybe not due to the separator since this is connected before the throttle body.

Have you checked your EGR?

 

[ajsellors]

Have the same error. How was access to the separator and removal - easy?

As Jannes pointed out here in this forum, the System too lean is maybe not due to the separator since this is connected before the throttle body.

Have you checked your EGR?

Hi,

yes, I have read those posts but I am in the process of ticking things off so I am ruling things out at the moment.

The separator is easy to remove, you just need to lift the front of the car and remove the undertray. Its at the back of the engine and can be accessed from underneath. The 3 bolts have 5mm hex heads and it is easy to get a ratchet socket handle up and lower the separator down past the exhaust and driveshaft. On mine which is an early one, the pipe plugs into the back of the inlet manifold which can be accessed from the top of the engine. There is also an electrical plug for the heater element which can be easily disconnected.

Before refitting I'm wanting to know if the separator is Ok to go back. I don't know if there are meant to be any one way or pressure valves inside which might not be working anymore. The box just seams to allow airflow. If that is all it does then I will put it back, but if its broken inside then I want to know that I need to replace it.

Regarding the running issue, yes, there are other things on my list to check, including the EGR. The EGR should be OK but I haven't been lucky with those. When I got the car there was a cheap valve fitted which worked, but with a gasket which didn't. A new gasket sorted it until the valve broke. This was replaced by a Pierburg value. That failed just outside the guarantee so now I have another one! I'm not rulling that out, although there are no EGR errors recorded.

regards

Andrew

 

[Olerype]

Thanks alot; I have a new separator and EGR on the shelf. Just no time yet to do the job... Lambda and wiring is ok.

We should join forces to get rid of this error code.

 

[ajsellors]

I needed to leave it a couple of days to make sure before posting.
The oil separate is back on with new seals and the hose now clamped. It seems to fit better at the back of the engine and there is a grove in the inlet manifold that allows the hose to run diagonally down put of the way which puts it further away from things it can rub against than before.

I wasn't expecting much, as stated, the hose connects to the air intake before the throttle so shouldn't really do much. I didn't clean anything as it appeared to be all clear but its piece of mind to know that its OK.

After fitting I checked the mixture trim adjustment and it was still out the same amount as before. After 2 days driving the engine light is back on so I am not really surprised.

Next on the list, petrol EGR, should it suck?

https://www.a2oc.net/community/index.php?threads/1-4-petrol-egr-should-it-suck.37574/

Andrew

 

[ficanas]

Just did that job yesterday, after a 10 years ECP + motor signal.

Teared down the oil box separator, cleaned it, the throttle body (very dirty), cleaned as well, swapped the 2 hoses for brand new ones.

The oil separator's seals was cooked, hard as glass, and they broke when I removed them... Fitted a pair of brand new ones.

Started the car, like attended, ECP was over. After 4/5 restarts, motor light was over too! Hope it will stand!

Didn't run a diag, I will, but I guess it's useless.