New charge cooler needed

Tsixty

Senior Member
T6 Guru
Van been in Listers VW Coventry since first thing Monday morning to have a very small oil leak looked at from somewhere at the very top, front of the engine. I had naively assumed it might be a small pipe, oil seal or similar that needed doing somewhere at the top as the leak is quite minor, although I couldn't actually see where it was coming from. No update from the service centre by 4.30pm Monday so I called them to be told it is on the ramps, which I interpreted as we have only just got round to looking at it.....

No phone call or update whatsoever from them yesterday, I was busy all day and forgot to chase them up until it was gone 5pm so didn't bother as it obviously wasn't going to be ready.

Just called them for an update, good news they say, the part has arrived so we now need to get it fitted but we aren't sure if we have any spare ramp time today o_O

Oh it needs a new part then says I, what part is that? Reply, it needs a new charge cooler (it is a BiTDI) :oops:.

Not what I was expecting. Again it might be my naivety, lack of technical knowledge, or both but I'm struggling to envisage why engine oil would be anywhere near the charge cooler, that is unless it came up from the turbos?

Warranty work fortunately as 18 months old and 11k miles.

Separate point but not overly enamoured with their customer service either.
 
You are correct, I would make further enquiries.
The crankcase breather vents into the inlet side of the turbocharger, unless the turbo oil seal has failed that is the only route to allow oil into the induction that I’m aware of.
 
Did they mean charge cooler or oil cooler?
As you guessed there is only air and water in the charge cooler.
 
Did they mean charge cooler or oil cooler?
As you guessed there is only air and water in the charge cooler.

absolutely no doubt they said it was the charge cooler. Where the oil was visible it was directly below the charge cooler, there were small pools of oil there. Annoyingly I didn't take any pictures of it before it went in.
 
So it's back and as expected new charge cooler fitted. I asked how it could be that the charge cooler had oil in it and got a very stand offish shrug of the shoulders from the service advisor. I pushed a bit harder and eventually got them to read out the technician's notes to me, they wouldn't let me see them or let me have a print out of them. What follows is how I best heard their fast talking through a mask while I tried to jot down notes:

Visual inspection of engine area
Engine oil apparent around charge cooler mounting bracket
Checked symptoms on estis/etis/esti (couldn't work out what this word was)
Followed diagnostic procedure on.... (the thing beginning with e )
E..?. confirms charge cooler needs replacement
Followed e..?. service procedure to replace charge cooler
Connected vehicle to external power supply
Ran e..?. charge cooler water pump diagnostic routine
Charge cooler water pump diagnostic complete.

That’s it. I couldn't get any more out of them.

Picture is the new part fitted. I have circled where the pools of engine oil had accumulated before the replacement.
Polish_20201014_211040696.jpg
 
So the oil must have been from the engine breather that feeds into the intake and that must condense and collect in the charge cooler and then get forced out if the charge cooler has a crack?
 
So the oil must have been from the engine breather that feeds into the intake and that must condense and collect in the charge cooler and then get forced out if the charge cooler has a crack?
Loz, I don't know it is beyond my knowledge level. But I observed 2 things, firstly the whole thing was presented very much as an easy diagnosis, a done deal. The way the technician's notes sounded when read back to me was that whatever procedure was followed it was run of the mill, if you find oil here then replace the charge cooler because that's what it will be. Secondly, the van sounds slightly different I'm sure of it. So much so that I had the radio off all the way home listening to it.

I wish I could have looked at the charge cooler that came off. It looks like a pretty expensive part as well.
 
As far as I‘m aware the only way the diagnostics would pick up a leaking charge air cooler would be on differential pressure / temperature irregularities, I imagine it would need to be a fairly big leak which might indicate why the newly fitted charge air cooler sounds different??
I’ve mentioned oil breather mist carry over before as being a partial cause of EGR fouling, this seems to indicate that there is a significant oil mist that would be worth separating out before the induction. An oil coating will also reduce the heat transfer rate, not good for a cooler.
 
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Back in the day I had a Nissan xTrail. The intercoolers in these were regularly changed because of oil leaks. I suspect they were just steam cleaned and given to the next customer with a ‘leaking ‘ intercooler. Nissan eventually came out with a software fix which reduced boost pressure and lost about 20 Bhp. I didn’t, keep the car after the warranty ran out because I expected the true cause of the oil leak would be revealed as ‘Oh you need at new turbo Sir!’
 
So it's back and as expected new charge cooler fitted. I asked how it could be that the charge cooler had oil in it and got a very stand offish shrug of the shoulders from the service advisor. I pushed a bit harder and eventually got them to read out the technician's notes to me, they wouldn't let me see them or let me have a print out of them. What follows is how I best heard their fast talking through a mask while I tried to jot down notes:

Visual inspection of engine area
Engine oil apparent around charge cooler mounting bracket
Checked symptoms on estis/etis/esti (couldn't work out what this word was)
Followed diagnostic procedure on.... (the thing beginning with e )
E..?. confirms charge cooler needs replacement
Followed e..?. service procedure to replace charge cooler
Connected vehicle to external power supply
Ran e..?. charge cooler water pump diagnostic routine
Charge cooler water pump diagnostic complete.

That’s it. I couldn't get any more out of them.

Picture is the new part fitted. I have circled where the pools of engine oil had accumulated before the replacement.
View attachment 88182
What's most disappointing to me is that there's technical people working in VW dealerships who had to run an electronic check on a mechanical part!

What's the world coming too, next they'll be running a diagnostic to say your exhaust is blowing or you've got a puncture.

FWIWs a charge cooler is only full of two things, air and coolant. If there's oil in there then it's sod all to do with the charge cooler, the new one will do the same again. DXX is on the money :thumbsup:
 
As far as I‘m aware the only way the diagnostics would pick up a leaking charge air cooler would be on differential pressure / temperature irregularities, I imagine it would need to be a fairly big leak which might indicate why the newly fitted charge air cooler sounds different??
I’ve mentioned oil breather mist carry over before as being a partial cause of EGR fouling, this seems to indicate that there is a significant oil mist that would be worth separating out before the induction. An oil coating will also reduce the heat transfer rate, not good for a cooler.
I don't think it was electronic diagnostics that picked anything up as such, it was more that the diagnostic/fault finding tool that was being used basically was being followed step by step and it said if you get evidence of oil contamination here and here then remove the mechanical part (the charge cooler), then check for oil here and here and if you find it the diagnosis is complete you need to change the charge cooler.

I'm seriously doubting that there was a big leak in it because I would have thought I would have noticed a performance or economy detriment, which I hadn't? The noise difference was very subtle.

Who knows. Monitor it and see what happens over the next few months I suppose, particularly watching to see if oil starts to appear in the same place as before.
 
The reason they run electrical checks etc for what you described is for Warranty purposes. If they didn`t VW can easily reject the claim and the Dealer is left with the Parts/ Labour bill. They need to print out the Guided fault finding to prove they followed VW procedures. I worked in VW Comm Dealer in the past.
 
for cross reference, similar issue here:





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