Passat 1.9TDI Turbo

Buford T Justice

Hi

02 Passat 1.9 TDI RedI. 100 BHP according to cartell. Couldn't get the engine code.

Anyhow, the turbo appears to have failed. The car starts and idles fine, but if you rev it up to where the turbo kicks in, you can hear what sounds like the bearings in the turbo grinding or rubbing more than they should be. The engine loses power, and there is black smoke out of it. Not acrid black smoke, but black enough to be visible.

I think the turbo's had it, but it doesn't seem like the seals have failed oddly.

Also the heater plug light is flashing intermittently on the dash when the car is running.

Can some boffins here give me some pointers or their opinion?

Ta

shamwari

When turbo bearings go, the turbos usually start to whistle loudly before whining. If you can get your finger at the impeller (with the engine stopped) and rock it to see how much play it has, you will have an idea of how worn it is. If the noise is more of a drone then it could be a damaged hose or holed intercooler, and both will give you a noticeable power reduction and smoke. If the car has been properly serviced and driven, and isn't a mega-miler, then the turbo may be ok.

The flashing glowplug light is probably indicative of a fault condition being detected and will need a scan to see what's happening.

Buford T Justice

shamwari wrote: »

When turbo bearings go, the turbos usually start to whistle loudly before whining. If you can get your finger at the impeller (with the engine stopped) and rock it to see how much play it has, you will have an idea of how worn it is. If the noise is more of a drone then it could be a damaged hose or holed intercooler, and both will give you a noticeable power reduction and smoke. If the car has been properly serviced and driven, and isn't a mega-miler, then the turbo may be ok.

The flashing glowplug light is probably indicative of a fault condition being detected and will need a scan to see what's happening.

Thanks for that. I'll stick the odbII on it next week and see what the glow plug light is all about.

Now that you mention it. When you rev it up, it sound like a whistle, but my first instinct would have been a bearing whine. The owners have said that it was down with some local fella to get it looked at before. He said there was a hole in the inter-cooler and was supposedly fixed / plugged. Wondering would it be worth replacing the inter-cooler with a S/H one before going down the turbo line. Will get my fingers into it next week and see if there is any play in the impeller.

I assume you are talking about vertical and horizontal play in the same way there would be play in a wheel bearing that needs replacing?


The people that own it are farmers and its certainly hasn't been kept clean but wouldn't get major abuse. Not a mega miler for its age, only 150K on the clock.

shamwari

There will be a small amount of play in the impeller, but if it rocks all over the place then it may well be shot. Look closely at the impellers tips with a torch, and if they are bent like they have been making contact with the casing then you know where you stand

From what you say above, I wonder if the intercooler repair was bodged, or if there is a loose or leaky intake hose somewhere - especially if there is a lot of oil about.....

Alan70

Hi, turbo went on my 06 passat last year. Symptoms was siren like sound upon acceleration. Walsh motors in belfast got recond unit for me for I think 500euro.

Tea drinker

some passaters claim the turbo fails it sounds like a dentists drill, it can happen very suddenly...

Buford T Justice

Ta.

I've had a listen in the engine with someone else revving it up and the noise is from the passenger side of the engine, and not the drivers side. So I don't think its the turbo. Will have a look tho.

I rekon the intercooler patch was bodge or there's a loose pipe or something similar. Will have it up on a lift tomorrow to have a looksie.

Buford T Justice

Ok. Had a look under the car today and as was suspected here, the lower pipe to the intercooler was off. (The pipe feeding the air into it)

Looks like the back spud to lock the intercooler into the car (see diagram below) broke off and there was a bodge fix to patch the hole. I've looked into it, and it all seems ok
I put it back on and locked into the socket but once the turbo kicked in at 3k revs, it blew the pipe off again.

So the pipe feeding the air to the intercooler keeps blowing off, which would lead me to believe that the intercooler would be blocked somehow but I can't see anything in it causing a problem.

Is there likely to be a blockage further up the line, or what would be causing the pipe to blow off? The pipes look to be locked in securely.

Thanks

Slidey

It is not a blockage.

There is a lot of air heading into that pipe under load. That is what is blowing it off.

My Golf blew a pipe off one night on me and I tired to tie it back into place using large cable ties. It snapped them as soon as it hit boost.

Buford T Justice

Slidey wrote: »

It is not a blockage.

There is a lot of air heading into that pipe under load. That is what is blowing it off.

My Golf blew a pipe off one night on me and I tired to tie it back into place using large cable ties. It snapped them as soon as it hit boost.

What's the solution then? or what worked for you?

beretta686s

used to happen to my o4 transporter in work made up a clamp o hold the to pipes together still going strong since

Buford T Justice

I had another look around under the bonnet yesterday evening and I managed to get the intercooler pipes held on with some jubilee clips. The heater plug light starts flashing on the dash when the revs go up.

The intercooler pipes are staying on, but at about 3.5k revs she will splutter a bit and lose power. I'm thinking that the patch on the intercooler isn't working right and the power loss is due to a leak.

Any Suggestions?

nogoodnamesleft

It could well be that there is still air leaking before entering the manifold of the intercooler. You can get a good look at the core of the intercooler from underneath.

It might be more prudent to replace the rubber pipe to ensure its not leaking any further. Its about 50 quid from the dealer which includes new rubber o rings and clips to ensure an airtight fit.

The hose is a lot cheaper than an intercooler!

Buford T Justice

Was thinking about that alright. Its most likely a loss of air through a leak that's causing the problems is it?

voxpop

I got a smoke test done on mine, just to see if there were any leaks - might be worth getting it done before you go replacing pipes. Usually the pipes are held in place with a metal clip and 2 notches on the adjoining pipe. These notches can get worn causing the pipe to blow - might be worth checking the blowing pipe to see if the notches are worn.

Also If your intercooler has a hole - you will know it because it will drip oil

Buford T Justice

voxpop wrote: »

I got a smoke test done on mine, just to see if there were any leaks - might be worth getting it done before you go replacing pipes. Usually the pipes are held in place with a metal clip and 2 notches on the adjoining pipe. These notches can get worn causing the pipe to blow - might be worth checking the blowing pipe to see if the notches are worn.

Also If your intercooler has a hole - you will know it because it will drip oil

They are worn, which I think is why its blowing off the pipe. In relation to the hole, I had the intercooler out and put it back in. I took it for a spin and checked it again and there was fresh oil around the edges of the metal plate that was riveted in as a patch. This the likely culprit?

voxpop

Fingers McGee wrote: »

They are worn, which I think is why its blowing off the pipe. In relation to the hole, I had the intercooler out and put it back in. I took it for a spin and checked it again and there was fresh oil around the edges of the metal plate that was riveted in as a patch. This the likely culprit?

For that metal plate - I would try getting some liquid metal (oil resistant), clean and sand around the edges of the plate and apply the liquid metal. It might be enough to seal her up.

Buford T Justice

Where am I likely to pick some up? Or do you mean something like a two part epoxy resin?

Do you know a brand name??

I know there is stuff you can get in an auto factors in a roll that you mix together that sets like concrete.

voxpop

This is what I used before on a small hole - didnt know if it would hold but it did - got it in homebase

Buford T Justice

Excellent. Will give that a bash this evening. Thanks for that.

shamwari

When you drive the car, does it go into limp mode when the glowplug light starts flashing?

Slidey

Waste of time I would say.

Look for a good 2nd hand intercooler and if they have good pipes get them. You'll know if the pipes are knackered by inspecting the 2 indentations

Buford T Justice

shamwari wrote: »

When you drive the car, does it go into limp mode when the glowplug light starts flashing?

Nope, I think it might be down to the brake pedal switch. I spotted the brake lights were staying on in the car yesterday evening when I was out of the car. Will look at it again, but it seems to be the culprit.

Slidey wrote: »

Waste of time I would say.

Look for a good 2nd hand intercooler and if they have good pipes get them. You'll know if the pipes are knackered by inspecting the 2 indentations

Been ringing around today. Every breaker I rang only wants to sell new ones to me, and they are ranging from £65 + VAT to €150 + VAT. Oddly none of the breakers have the hoses to sell to me.

Since I don't have the chassis number to hand, I was told by conollys that they can't give me a price for the hose, as it ranges from €45 to €250 + VAT for them - For a feckin hose!

Didn't think it'd be that difficult to come across a second had one of these. As a result, I'll give this a shot first. My preference would be to get a s/h intercooler or a new one and worst case, I can have one down from treanors next Wednesday so I have until Tuesday to fiddle with whats there.

darragh o meara

If the pipe keeps coming off the intercooler get a mikolar clip ( better than a jubilee clip as it applies equal pressure all the way round) when I worked with mercedes it was a common problem and the mikolar clips come recommended by the factory.

If the intercooler is leaking its best to replace before you cause damage to the engine.

Buford T Justice

Mikolar clip won't make a difference. The intercooler pipes lock into the intercooler itself, they don't slot over it.

Anyhow, the patch didn't work (surprise surprise). I hope to have a new one on monday to refit it.

Got the codes read today on autoboss and it came up with 5 for the engine

P1570 - Engine Control Unit Disabled
P1256 - Engine Coolant Temperature Sensor G62 Open. Short Circuit.
P0571 - Load signal from Alternator Term. DF: Range/Performance / Implausible Signal
P1557 - Charge Pressure Control: Positive Deviation (Due to the leaky intercooler i hope)

I Cleared them all and re-scanned and all that came back was the brake pedal switch. Hopefully, new hoses and an intercooler in the next few days and jobs oxo

shamwari

Fingers McGee wrote: »

Mikolar clip won't make a difference. The intercooler pipes lock into the intercooler itself, they don't slot over it.

Anyhow, the patch didn't work (surprise surprise). I hope to have a new one on monday to refit it.

Got the codes read today on autoboss and it came up with 5 for the engine

P1570 - Engine Control Unit Disabled
P1256 - Engine Coolant Temperature Sensor G62 Open. Short Circuit.
P0571 - Load signal from Alternator Term. DF: Range/Performance / Implausible Signal
P1557 - Charge Pressure Control: Positive Deviation (Due to the leaky intercooler i hope)

I Cleared them all and re-scanned and all that came back was the brake pedal switch. Hopefully, new hoses and an intercooler in the next few days and jobs oxo

Code wise, them look like old codes, possibly when previous repair attempts were undertaken with leads disconnected...

Buford T Justice

Sorry, I left one off the list

P0571 - Brake Switch - Circuit Malfunction.

Its the only recurring fault, so the only one I'm bothered about. Should have a new one to stick in tomorrow, and have a new intercooler then. hould fix the lot fingers crossed.

Buford T Justice

Ok, so one new intercooler and pipe later, the leaky turbo is now fixed.

She is now, however taking herself into limp mode occasionally when you are driving, and its not necessarily when the revs are that high.

For example, if you thrash it out in second and third its not a problem. If you're tipping away in fourth and starting to move on, it may hop into limp mode. A quick on / off of the key resets it temporarily.

According to Autoboss, the code I'm getting is P1557: Turbocharger overboost control limit exceeded. As the off on with the key resets limp, I don't think its the MAP. I think the vanes in the turbo are sticking causing the problem.

Without having to go through the trouble of removing the turbo from the car, is there a cleaner that can be used to shift the carbon deposits?

Halfords have this stuff, but is it worth it?

Any advice / suggestions as always appreciated.

shamwari

Yep, overboost is usually the veins of a VGT turbo stuck in the max boost position. I'm almost certain that there's no wastegate on them things, and that the excess boost pressure is moderated by adjusting the pitch of the vanes in the turbo. There should be an external rod or linkage that performs this adjustment, and you might be able to free up the vanes by working the linkage between the limits of its normal range of movement.

I've never cleaned a VGT turbo and have no experience of using the stuff from Halfords you mention. But I suppose its worth a punt as its cheaper than shelling out for a replacement blower.

Buford T Justice

Nah, no wastegate on a VGT Turbo.

Below is a screenshot of VW's Elsawin showing the breakdown of the turbo. Click for larger



and this is from vagcat.com.



Can anyone tell me where the linkage is, I can't see it, unless its built into the 11, which is the pressure unit in the first image. Couldn't spy it on the turbo today, but i can always have a harder look.

voxpop

I think it is 11 in the first pic - its vacuum actuated

Ive a link below to a pdf from tdiclub - its about removing the turbo and servicing it. This was on a jetta so slightly different but give a good idea of how the turbo works and how much work is involved in cleaning it up.

turbo removal and cleaning pdf


Edit: Found a youtube vid of the actuator actuating - you might be able to get some needle noise pliers in there and move the rod.

https://www.youtube.com/watch?v=s7lNE95jJy4

Buford T Justice

Thanks everyone.

That stuff i tried was useless, but hey maybe it'll help with consumption or something :rolleyes:

Anyhow, I whipped out the turbo today and dismantled the exhaust side of the manifold and cleaned it all down.

It was obvious that they were sticking as when I took off the actuator and tried to move the vanes manually, it didn't move very much. Its actually simple enough to take apart and clean, but you need a bit of patience to re-assemble it properly to make sure it works right.

Shoved it back on the car and took it for a spin. Its brilliant - goes like a shot now. If you are mechanically minded and good with you're hands then its worth doing if you are going into limp mode.

Below is another link of another breakdown of how to do it. I would have been lost without these.

http://kev-stuff.blogspot.com/2007/01/vnt-turbo-de-coke.html