2.0 tdi 16v Turbo issues

[mitsiboyblue]

Hi all, unsure if im posting this in the right place but OMG im i having some turbo problems. I've bought this A3 diesel 2.0 tdi 2007 with a blown turbo.
Its now had 3 turbo cores all balanced and the last was also flow tested. But the turbos fail if i drive reasonably hard.
Shearing the compressor wheel off then as the main shaft is insecure , hemorrhaging all the supplied engine oil down into the exhaust.
Each time ive completely stripped, cleaned out everything which is costing me a fortune in parts and lost time.
There has never been any engine fault codes or warning lights and when it does drive, it drives beautifully with plenty of power.
Has anyone else had this problem and how did it get resolved? as now it is on its 4th turbo core and i will not drive it over 3000rpm for fear it will happen again.
Dave O

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[DJ_26]

Hi all, unsure if im posting this in the right place but OMG im i having some turbo problems. I've bought this A3 diesel 2.0 tdi 2007 with a blown turbo.
Its now had 3 turbo cores all balanced and the last was also flow tested. But the turbos fail if i drive reasonably hard.
Shearing the compressor wheel off then as the main shaft is insecure , hemorrhaging all the supplied engine oil down into the exhaust.
Each time ive completely stripped, cleaned out everything which is costing me a fortune in parts and lost time.
There has never been any engine fault codes or warning lights and when it does drive, it drives beautifully with plenty of power.
Has anyone else had this problem and how did it get resolved? as now it is on its 4th turbo core and i will not drive it over 3000rpm for fear it will happen again.
Dave O

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I'm wondering if your car may have been remapped poorly in the past. It may be possible that there is a huge boost spike written into the map and this is what's killing the turbo. Then again could be something else altogether. Your best bet is to take it to someone to see the logs of the car running, so boost pressure etc. Then they can see what conditions the engine is running in when you go above 3000rpm and then hopefully use that information to get an idea of where to start looking.

 

[mitsiboyblue]

I'm wondering if your car may have been remapped poorly in the past. It may be possible that there is a huge boost spike written into the map and this is what's killing the turbo. Then again could be something else altogether. Your best bet is to take it to someone to see the logs of the car running, so boost pressure etc. Then they can see what conditions the engine is running in when you go above 3000rpm and then hopefully use that information to get an idea of where to start looking.

That would explain why its got loads of power the turbos are failing and there has never been any EML warning lights, no limp nothing.

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[ayfreetee]

Possibly actuator fault, not closing properly, would over speed the turbo, dumping the boost off down the exhaust, did you replace the actuator?

 

[JimS3]

Did you replace the oil feed pipe to the turbo and check the pickup pipe in sump?

I had a replacement turbo last about 3 miles due to lack of oil pressure to it.

 

[mitsiboyblue]

Actuator was tested and working fine so when back on. the ajusting screw thread still has the factory paint marks on it and its never been touched that i can see.

Possibly actuator fault, not closing properly, would over speed the turbo, dumping the boost off down the exhaust, did you replace the actuator?

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[mitsiboyblue]

Did you replace the oil feed pipe to the turbo and check the pickup pipe in sump?

I had a replacement turbo last about 3 miles due to lack of oil pressure to it.

Yes oil pipe was replaced with new stainless steel, oil return pipe including sump all been taken off cleaned all gone back fine. The turbo is holding out at the moment but i dont take it over 3000rpm for fear of the turbo failing again. its just not a car i have much faith in at the moment unless i find out some more information.

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[mitsiboyblue]

Actuator was tested and working fine so when back on. the ajusting screw thread still has the factory paint marks on it and its never been touched that i can see.

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Over speeding the turbo is definitely a related factor by examining the compressor wheel.
At first i though yes its cheap turbo cores.
but later.... thats not possible because they're all from different suppliers and up to now ive fitted 3 cores, fresh oil and filters each time.

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[JimS3]

Have you logged actual vs requested boost with VCDS or similar? If it has adequate oil pressure then shearing the compressor wheel does sound like overspinning.

Did you clean the VNT mechanism and ensure it operated smoothly when fitting the cores?

TBH, fitting a non genuine core to a VNT turbo and then not setting up the actuator properly is asking for trouble. At Garrett when the original turbos are produced each turbo is setup on a computerised rig and calibrated individually. The non genuine cores could be flowing completely differently to a genuine one.

I will no longer fit reman turbos, had too many issues with them.

A genuine Garrett can be found for around £500 inclusive of you shop around and should have a 2 year guarantee.

Only logging your current setup will reveal what is going on.

 

[ayfreetee]

A recon turbo can be had from a British turbo specialist on eBay , complete with flow bench printout and two year guarantee for about £300 exchange.

 

[mitsiboyblue]

Hi there, the first two cores that i fitted were with the original VGT mechanism and the control accuator was never touched as i assumed it was matched as you say to the VGT/VNT.
the third turbo core was fitted with a brand new VGT/VNT mechanisum due to sustaining too much damage from the previous failures and then sent to a turbo specialist near me who assured me they will speed test and set up 'Including Flow Testing' because of the concerns of over spinning.
I haven't done any logs to find out what the actual and requested boosts from ECM are. But it is something i need to do. If anyone can tell me of a trusted tunner would be greatly appreciated though.
I've lost confidence at the moment but happy to keep running it up to 3000 rpm max while i search for the solution from all you guys.
I'm a Mitsubishi Master Technician and a little embarrassed to say the least about this repeated problem as ive never had compressor wheels sheering off on any of the Ralliart /Evo's ive tuned over the years but they are bigger units and designed to handle more power anyway.
I guess theres a lot to be said about product knowledge in this instance.

Have you logged actual vs requested boost with VCDS or similar? If it has adequate oil pressure then shearing the compressor wheel does sound like overspinning.

Did you clean the VNT mechanism and ensure it operated smoothly when fitting the cores?

TBH, fitting a non genuine core to a VNT turbo and then not setting up the actuator properly is asking for trouble. At Garrett when the original turbos are produced each turbo is setup on a computerised rig and calibrated individually. The non genuine cores could be flowing completely differently to a genuine one.

I will no longer fit reman turbos, had too many issues with them.

A genuine Garrett can be found for around £500 inclusive of you shop around and should have a 2 year guarantee.

Only logging your current setup will reveal what is going on.

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[mitsiboyblue]

Hi there, the first two cores that i fitted were with the original VGT mechanism and the control accuator was never touched as i assumed it was matched as you say to the VGT/VNT.
the third turbo core was fitted with a brand new VGT/VNT mechanisum due to sustaining too much damage from the previous failures and then sent to a turbo specialist near me who assured me they will speed test and set up 'Including Flow Testing' because of the concerns of over spinning.
I haven't done any logs to find out what the actual and requested boosts from ECM are. But it is something i need to do. If anyone can tell me of a trusted tunner would be greatly appreciated though.
I've lost confidence at the moment but happy to keep running it up to 3000 rpm max while i search for the solution from all you guys.
I'm a Mitsubishi Master Technician and a little embarrassed to say the least about this repeated problem as ive never had compressor wheels sheering off on any of the Ralliart /Evo's ive tuned over the years but they are bigger units and designed to handle more power anyway.
I guess theres a lot to be said about product knowledge in this instance.


Sent from my SM-G930F using Tapatalk

Hi there, the first two cores that i fitted were with the original VGT mechanism and the control accuator was never touched as i assumed it was matched as you say to the VGT/VNT.
the third turbo core was fitted with a brand new VGT/VNT mechanisum due to sustaining too much damage from the previous failures and then sent to a turbo specialist near me who assured me they will speed test and set up 'Including Flow Testing' because of the concerns of over spinning.
I haven't done any logs to find out what the actual and requested boosts from ECM are. But it is something i need to do. If anyone can tell me of a trusted tunner would be greatly appreciated though.
I've lost confidence at the moment but happy to keep running it up to 3000 rpm max while i search for the solution from all you guys.
I'm a Mitsubishi Master Technician and a little embarrassed to say the least about this repeated problem as ive never had compressor wheels sheering off on any of the Ralliart /Evo's ive tuned over the years but they are bigger units and designed to handle more power anyway.
I guess theres a lot to be said about product knowledge in this instance.

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[JimS3]

Having changed the VNT ring too you have changed way too much for that turbo to be boosting correctly. These turbos really are so finicity. Every remanufactured unit I have ever logged has has been out of spec, they may seem to work ok, but the requested and actual boost deviate considerably, especially around spool up time.

These turbos also don’t have a very big safety margin and are working near their limits as standard. That’s not Audi being cheap, but fitting a small turbo so it spools at low rpm.

I really think your only next stage is to get hold of VCDS and log both the requested and actual boost, and the injection quantity to see if it’s been tuned.

Then you can establish if it’s the map or bad turbos at fault.

 

[mitsiboyblue]

Thankyou very much for all your advice, its always good to hear from someone who more knowledge as I'm always ready to learn. I will look into this equipement and get some logs.
JimS3
Dave O

Having changed the VNT ring too you have changed way too much for that turbo to be boosting correctly. These turbos really are so finicity. Every remanufactured unit I have ever logged has has been out of spec, they may seem to work ok, but the requested and actual boost deviate considerably, especially around spool up time.

These turbos also don’t have a very big safety margin and are working near their limits as standard. That’s not Audi being cheap, but fitting a small turbo so it spools at low rpm.

I really think your only next stage is to get hold of VCDS and log both the requested and actual boost, and the injection quantity to see if it’s been tuned.

Then you can establish if it’s the map or bad turbos at fault.

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