MK3 1.8 Leon Turbo help

[CM94]

Hey all, made a post some time ago about a metallic/rattling noise and it turns out my turbo is on the way out.

I'm stuck on what to do and was wondering if anyone's replaced or upgraded their turbo for the MK3 1.8.

I'm currently juggling two options.

Buy a factory replacement turbo which seems to run around anything from £1000+ for just the turbo

Or whilst I'm at it fit a better one?

So I guess my question is, is it even worth getting an upgrade? Can a manual 1.8 handle it? ..

Thanks for reading!

 

[SuperV8]

Looking at a 2014 1.8t Leon on autotrader as an example it has an MQ250 (the 250 is associated with the torque limit) gearbox and a smaller 228mm clutch - vs the MQ350 and 240mm clutch of the 2.0tsi's.

If you look at fitting a bigger turbo I think you'll need to also factor in a new gearbox/clutch.

Personally I would look at getting your turbo re-built - as an example:

SEAT - Precision Turbo Services

precisionturbos.co.uk

 

[CM94]

Looking at a 2014 1.8t Leon on autotrader as an example it has an MQ250 (the 250 is associated with the torque limit) gearbox and a smaller 228mm clutch - vs the MQ350 and 240mm clutch of the 2.0tsi's.

If you look at fitting a bigger turbo I think you'll need to also factor in a new gearbox/clutch.

Personally I would look at getting your turbo re-built - as an example:

SEAT - Precision Turbo Services

precisionturbos.co.uk

Thanks! For some reason I didn't even think about a rebuild!

 

[nanobis]

Looking at a 2014 1.8t Leon on autotrader as an example it has an MQ250 (the 250 is associated with the torque limit) gearbox and a smaller 228mm clutch - vs the MQ350 and 240mm clutch of the 2.0tsi's.

If the car is manual like he's mentioned it, then it won's have the MQ250 and wont be limited to 250 nm of torque with that gearbox. From what I found when researching my car (1.8 FR DSG) the engine was purposely "detuned" to work with the MQ250 Reliability.

So I guess my question is, is it even worth getting an upgrade? Can a manual 1.8 handle it? ..

I'm by far no expert in these cars/engines but from what i've seen online the the same EA888/CSJA engine is very capable of tuning, and is in quite a few VWAG cars, with a stage 4 tunes up to 400+ bhp. How easy and cheap it is to achieve is different matter.

For me 180bhp is more that enough power, after spending the last 7 years with 95bhp 1.6L Focus TDCI. and Fiat Doblo 1.9L turbo diesel 115bhp

 

[SuperV8]

If the car is manual like he's mentioned it, then it won's have the MQ250 and wont be limited to 250 nm of torque with that gearbox. From what I found when researching my car (1.8 FR DSG) the engine was purposely "detuned" to work with the MQ250 Reliability.




I'm by far no expert in these cars/engines but from what i've seen online the the same EA888/CSJA engine is very capable of tuning, and is in quite a few VWAG cars, with a stage 4 tunes up to 400+ bhp. How easy and cheap it is to achieve is different matter.

For me 180bhp is more that enough power, after spending the last 7 years with 95bhp 1.6L Focus TDCI. and Fiat Doblo 1.9L turbo diesel 115bhp

Incorrect!
The manual 1.8tsi uses an MQ250!
The DSG 1.8tsi uses an DQ200!

Both of which are fitted to engines with limited torque outputs of less than 250Nm.
Yes - the 1.8 can be highly tuned - BUT it is very limited by its drivetrain!

 

[CM94]

If the car is manual like he's mentioned it, then it won's have the MQ250 and wont be limited to 250 nm of torque with that gearbox. From what I found when researching my car (1.8 FR DSG) the engine was purposely "detuned" to work with the MQ250 Reliability.




I'm by far no expert in these cars/engines but from what i've seen online the the same EA888/CSJA engine is very capable of tuning, and is in quite a few VWAG cars, with a stage 4 tunes up to 400+ bhp. How easy and cheap it is to achieve is different matter.

For me 180bhp is more that enough power, after spending the last 7 years with 95bhp 1.6L Focus TDCI. and Fiat Doblo 1.9L turbo diesel 115bhp

Thanks for the reply also Super V8 for the extra clarification!

My bad luck decided to double down and my water pump is leaking as well so it'll be recon turbo and water pump. Ouch!

To be fair I've never felt lacking in the 180 but wouldn't mind extra! I had a Clio 200 prior and loved every second of it! Miss it so much!

 

[nanobis]

Incorrect!
The manual 1.8tsi uses an MQ250!
The DSG 1.8tsi uses an DQ200!

Both of which are fitted to engines with limited torque outputs of less than 250Nm.
Yes - the 1.8 can be highly tuned - BUT it is very limited by its drivetrain!

Well that's fair enough. But goddam VWAG (and other car makers) using similarly named products with silly number letter combinations. At least it's a short one. They all look confusing for someone with dyslexia.

You'd have thought they would only do this money pinching on few lines in terms of tolerances. But I guess they got to have a reason to sell the bigger more powerful versions. Just like Subaru and their STI/WRX lineups and "glass" gear boxes. (There's probably more but that's the only one I can think of right now)

 

[SuperV8]

Well that's fair enough. But goddam VWAG (and other car makers) using similarly named products with silly number letter combinations. At least it's a short one. They all look confusing for someone with dyslexia.

You'd have thought they would only do this money pinching on few lines in terms of tolerances. But I guess they got to have a reason to sell the bigger more powerful versions. Just like Subaru and their STI/WRX lineups and "glass" gear boxes. (There's probably more but that's the only one I can think of right now)

With the current focus on emissions, efficiency & cost I can understand why they don't fit the larger/heavier & more expensive clutches and gearboxes to their mid torque/price engines.
There are forums for every manufacturer for enthusiasts discussing what their drivetrains can/can't take! You will usually find the clutches are the 'weak' link (fuse) by design - to save the gears - much cheaper to change a clutch than a gearbox!

 

[Mo_86]

What are the tolerances for the DQ381?

 

[SuperV8]

From darkside developments:

From TVS:

 

[Mo_86]

Not bad

 

[SuperV8]

Yes they look like they are 'stout'!
Though a guy at work just this week, has had his throw a fault code - in his 2018 Passat TDI with the same DQ381 DSG - one of the pressure sensors in the mechatronic is faulty when hot so it stops all the even gears working! - could be expensive if you have to have someone else fix it.

 

[Mo_86]

Yes they look like they are 'stout'!
Though a guy at work just this week, has had his throw a fault code - in his 2018 Passat TDI with the same DQ381 DSG - one of the pressure sensors in the mechatronic is faulty when hot so it stops all the even gears working! - could be expensive if you have to have someone else fix it.

From general driving? High miles?

 

[SuperV8]

Just unlucky. Not high miles - just a commuter car.

 

[Mo_86]

Just unlucky. Not high miles - just a commuter car.

Strange one, hopefully not common.

 

[nanobis]

With the current focus on emissions, efficiency & cost I can understand why they don't fit the larger/heavier & more expensive clutches and gearboxes to their mid torque/price engines.

I can't complain about any of that. Especially after VW's previous emissions scandal.

There are forums for every manufacturer for enthusiasts discussing what their drivetrains can/can't take! You will usually find the clutches are the 'weak' link (fuse) by design - to save the gears - much cheaper to change a clutch than a gearbox!

Tbh, yeah it's part of most of the mods folks do when chasing more power. And in a manual gearbox box it's usually not a massive job.
With my current car being my 1st Auto, and a DSG, from my very basic research before buying it the gear box was torque limited.
I believe it's a bit more complicated/expensive being a duel clutch system. I don't actually know if there's much in terms of upgrades or if its even worth doing, instead of fitting one from a different platform like the DQ381 or if that's even compatible/possible. I'm not planning to chase power, I just want the silly turbo/intake noises and a fun drive.

The Subaru gear box I mentioned early has been known to actually destroy gears over clutches but that what happens when you put 100-200 hp gains through a stock box, but if your a modded Subaru owner you usually popping head gaskets like candy, if YouTubers/internet are to be believed.

 

[TMorris123]

Looking at a 2014 1.8t Leon on autotrader as an example it has an MQ250 (the 250 is associated with the torque limit) gearbox and a smaller 228mm clutch - vs the MQ350 and 240mm clutch of the 2.0tsi's.

If you look at fitting a bigger turbo I think you'll need to also factor in a new gearbox/clutch.

Personally I would look at getting your turbo re-built - as an example:

SEAT - Precision Turbo Services

precisionturbos.co.uk

Hi there, Would you happen to know if the facelift mk3.5 1.8tsi 2018 manual also has the MQ250 gearbox, I am looking to uprate the clutch but now worrying that the gearbox also needs doing if i go too far with the power

 

[SuperV8]

Hi there, Would you happen to know if the facelift mk3.5 1.8tsi 2018 manual also has the MQ250 gearbox, I am looking to uprate the clutch but now worrying that the gearbox also needs doing if i go too far with the power

Yes - all the 1.8 manuals are using the MQ250.
The 2.0 190 is using a MQ350.

 

[TMorris123]

Yes - all the 1.8 manuals are using the MQ250.
The 2.0 190 is using a MQ350.

Thank you, Guess i will have to rethink my plans

 

[SuperV8]

Thank you, Guess i will have to rethink my plans

If you google MQ250 - there are reports of them holding up ok to higher outputs, clutch normally being the weak link.
Drivetrains are really susceptible to how they are used - lots of launches will kill many transmissions.
Depends what your plans are? I'm sure it would be find a fine road car with a simple remap - if you want to make a track/drag tool then maybe a Cupra would be a better foundation.