170 BRD Throttle Body oil weep

Matt275

Matt275

Registered User
Joined
Oct 1, 2023
Messages
598
Reaction score
687
Points
93
Location
Hampshire
Hi all,

Noticed this tonight, pretty fresh oil around the solenoid area. I noticed it the most wet where the gasket tab pops out of the join. You can also see where oil has dripped onto the alternator wiring loom. Not a huge amount of oil, but what's it telling me?

Would this perhaps explain my erratic idle when warming up and the nasty smelling smoke on idle when warming up? When it's doing this and I pull away on cold, the RPM's rapidly go up and down by about 200 rpm, as though I'm quickly on and off revving it, but I'm not, I'm just trying to hold steady sensible revs to pull away etc.

I pulled off the intercooler pipe, that's not split anywhere. and the oil doesn't appear to be coming from that boost pipe seal either.

Can I dismantle and clean out the throttle body part on the side....and good to go again, what's the box on the side of the body, is it a gearbox that moves the throttle plate?
Looks like this part, but would it be calibrated correctly?

justgermanparts.co.uk

Electronic Throttle Body Valve Assembly - Audi A4 1.9 2.0 TDI 03G128063J

Audi A4 throttle body assembly for the 1.9 and 2.0 TDI. Found in a variety of A4 B6 engines this throttle body replaces the OE part number 03G128063J
justgermanparts.co.uk justgermanparts.co.uk


TB5



TB1
TB2
TB3
TB4
 
Removed the throttle body last night and took off the side panel which exposes the plastic the gears. The gears were also soaked with oil. No idea how long it's taken for the oil to build up in there...but the gasket had gone out of shape hence I could see the oil leaking out of it.

It was all over the gears, the cover, inside the little motor housing, everywhere. So cleaned it all out with electrical cleaner and cotton buds etc. The gasket wouldn't sit as it had expanded, so I cut about half an inch out of the gasket and sealed it with a little bit of silicone. It's pretty much just a protection cover for the gears really.

The only was oil can get in there is through the throttle butterfly shaft, no other way.

I guess turbo's do have a fair amount of oil going through the intercooler pipes, the car doesn't burn oil so I'm happy the turbo is ok, But perhaps I have a build up of oil in one or both intercoolers....maybe there's a seal somewhere on the butterfly shaft that has failed, but I couldn't see one.

I'd say a teaspoon or so of oil dripped out of the part when I was separating the side cover off.
This was what I found, the gears / motor looked the same. Spraying the granny out of it with electrical cleaner did work brilliantly.



TB6
 
  • Like
Reactions: Gmac
Yep this is fairly standard. Just give it a clean out and seal it up best again as you can.

I don't know of a 'fix' for this. It's just one of those TDI things

Had to do it myself on more than one BRD/BRE engine in these
 
  • Like
Reactions: Matt275
tr7 said:
Yep this is fairly standard. Just give it a clean out and seal it up best again as you can.

I don't know of a 'fix' for this. It's just one of those TDI things

Had to do it myself on more than one BRD/BRE engine in these
Click to expand...
Wow someone has replied!
I could consider it as a catch can to a degree hahahha

So the engine doesn't seem to burn oil, but I do get a blue(ish) smoke whilst it's warming up on idle, makes the idle lumpy....then settles down once past about 65-70 degrees....did you get that on your BRD? It doesn't smoke immediately on cold start....it starts after about 5 mins of idling cold.

My possible theory is that over time the oil builds up in one or both intercoolers....over the years, so not noticeable on the dipstick. This oil then gets pushed through the hoses and ultimately into the throttle etc.
I do find a dribble of oil when I take off the throttle body boost pipe / intercooler hose - the oil is by the butterfly.

Is there a chance there's loads of oil in my intercoolers that has built up over the years (obviously not full) but worthy of taking off the bottom hoses and drain both intercoolers?
Possible half an inch of oil sitting at the bottom of both for example....

Or the rocker cover breather is sending oil into the cold side turbo intake?

I considered injector seals, but then surely it would smoke immediately after starting it where oil has drained into the cylinders overnight.

Many many threads from years ago to more recent, on tons of forums about the blueish smoke after about 5 mins cold idle, but not a single thread mentions a firm cause or fix, the threads go cold, seemingly with no resolution.
 
I’d definitely take the bottom hoses off the intercoolers and drain what you can, better still, if you can, get the intercoolers off the car and give them a flush out.
 
  • Like
Reactions: Matt275
Gmac said:
I’d definitely take the bottom hoses off the intercoolers and drain what you can, better still, if you can, get the intercoolers off the car and give them a flush out.
Click to expand...
Fairly easy to remove if I jack up one corner at a time and lower the undertray?
I seem to recall they are some sort of weird jubilee clip?
 
You must log in or register to reply here.
Top
Back