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Discussion Starter · #1 · (Edited)
Hi,

I was driving along yesterday and i started hearing a whining noise coming from the engine when I started to accelerate there was loads of blue smoke coming out the exhaust and whining noise turned in to rattling sound. Any ideas what this could be?

Thanks
 

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Discussion Starter · #3 ·
Blue smoke is oil burning. Rattling could be oil starvation, if you burned it all. Does it still have oil in it?
I think something inside the turbo has gone and oils passing through the exhaust. I was trying to check the turbo shaft today while i was under the car but I can't seem to get those 2 spring clips off i've even got the pliers with the gripped ends that makes it easier to take these clips off but there's no room to move. I did check the VNT actuator but that just feels stiff like it did before as it was going in to limp mode but it's the intake side i wanted to check. Either way i am getting a second hand turbo from Facebook or eBay and just bolting that on. The cars a daily driver and i can't afford to have it off road for too long.
 

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Discussion Starter · #4 ·
I've managed to find a turbo that's got the same ATD engine code but it's from an estate mk4 and mines a hatchback. The seller assured me that they all have the same engines but i just wanted to ask you guys if there will be any difference? I literally just want to straight swap it out to be honest.

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I've managed to find a turbo that's got the same ATD engine code but it's from an estate mk4 and mines a hatchback. The seller assured me that they all have the same engines but i just wanted to ask you guys if there will be any difference? I literally just want to straight swap it out to be honest.

Thanks
If its the same engine then its very likely that it will be the same turbo to but it would be as well to get the part number from yours and check against the one being offered to make sure.

Needed a replacement alternator for my Mk5 1.9Tdi recently and chatting to a mate he said he'd a later Mk6 1.4 TSI for breaking and I could have it for nowt if it was of use. A look at the VW partd manual suggested there was a good chance they were the same so I lifted the code off mine which he checked against the donor and sure enough they were the same. Just need to swap them this weekend.

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Discussion Starter · #6 ·
Am thinking of reusing the oil feed line when i refit the turbo i know a lot people recommend swapping it for a braided line but i simply cannot afford it at the moment. Is it really difficult to remove and would people recommend reusing it? I know it comes with a banjo bolt and two copper washers. Someone also recommended priming the the oil feed line before fitting but am not sure how to do that?

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Basically you just want to ensure you’re getting a good supply of oil to the turbo. I replaced all my oil lines with braided, but if you can’t you’ll just have to do the best you can to ensure the lines are clear. Maybe use compressed air/a pipe cleaner to check. I’d suggest new crush washers. IIRC, when I did mine I think I connected the feed line and left the return disconnected at the engine, then ran the starter to build oil pressure without the ignition connected (just disconnect the large circular connector on the RHS of the block), checked there was oil coming out of the return line and then bolted that back on to the block. It was a long time ago though. Pretty sure I used an oil can to fill up the turbo as well before I connected the lines. Most importantly though, build oil pressure as above before starting and no revving for a few minutes.
 

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Discussion Starter · #8 ·
Basically you just want to ensure you’re getting a good supply of oil to the turbo. I replaced all my oil lines with braided, but if you can’t you’ll just have to do the best you can to ensure the lines are clear. Maybe use compressed air/a pipe cleaner to check. I’d suggest new crush washers. IIRC, when I did mine I think I connected the feed line and left the return disconnected at the engine, then ran the starter to build oil pressure without the ignition connected (just disconnect the large circular connector on the RHS of the block), checked there was oil coming out of the return line and then bolted that back on to the block. It was a long time ago though. Pretty sure I used an oil can to fill up the turbo as well before I connected the lines. Most importantly though, build oil pressure as above before starting and no revving for a few minutes.
Thanks for the tips I appreciate it. I would of assumed that as long as all the lines are bolted back together properly and there is no leaks or blockages anywhere then the oil pressure would eventually build up after starting the car as long as your not revving or stressing the engine too much and just let it idle for a while but i could be wrong.
 

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I think it's really important not to run the turbo dry, even for a moment, so I've heard anyway, which is why they say you should prime it
 

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Discussion Starter · #11 ·
I just had a question for you guys l I've been reading quiet a few threads on here and on other golf forums and a lots of people recommend changing the oem oil feedline for a braided one when removing or changing the turbo but my question is, is it actually necessary to change it or is it just good practice?

I was looking at a braided line from helperformace and they say that oily deposits can build up inside over time and that can cause blockages but I would of thought once the engine is warm and oil is running through the feed line it would unlodge any blockages or deposits?

Sorry don't mean to read too much in to this but I've always been curious. I was suppose it would be best to speak to a VW technician.
 

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It would NOT unlodge all deposits and blockages, hence why people get turbos failing from oil starvation, and hence why some people have a brand new turbo fail within 100 miles of fitting it - because of starving the brand new turbo of oil too. Even a brand new OE/OEM line is better than reusing the old one.
 

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Discussion Starter · #13 ·
It would NOT unlodge all deposits and blockages, hence why people get turbos failing from oil starvation, and hence why some people have a brand new turbo fail within 100 miles of fitting it - because of starving the brand new turbo of oil too. Even a brand new OE/OEM line is better than reusing the old one.
I've decided not to risk it and ordered a new braided oil feedline should be here in the next day or two. The next issue I have is getting my car down to the mechanic, he works from home and I've got to drop it off this Friday. The car is blowing quiet a lot of smoke from the oil that's leaking through in to the exhaust, am just wondering if it's worth taking the risk and driving it down to him as i can't really afford to get someone to take it down on a trailer. Having said that I've read people say that the car ca runaway and start accelerating on it's own! I was thinking if i keep it in low gears and drive it as slow as possible i might be ok but who knows. It could potentially cause irreversible damage.
 

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I've decided not to risk it and ordered a new braided oil feedline should be here in the next day or two. The next issue I have is getting my car down to the mechanic, he works from home and I've got to drop it off this Friday. The car is blowing quiet a lot of smoke from the oil that's leaking through in to the exhaust, am just wondering if it's worth taking the risk and driving it down to him as i can't really afford to get someone to take it down on a trailer. Having said that I've read people say that the car ca runaway and start accelerating on it's own! I was thinking if i keep it in low gears and drive it as slow as possible i might be ok but who knows. It could potentially cause irreversible damage.
It can become a runaway diesel at any RPM. Pretty sure TDIs have anti-shudder valves that will prevent runaway, but I wouldn't risk it. Any chance you can get someone to flat tow you down there? Tow ropes only cost a tenner or so, and if it's not too far then you can take it slow. Engine off, ignition on, so you can steer and indicate as needed. Brake plenty in advance because you won't have any servo assistance.
 

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Discussion Starter · #15 ·
It can become a runaway diesel at any RPM. Pretty sure TDIs have anti-shudder valves that will prevent runaway, but I wouldn't risk it. Any chance you can get someone to flat tow you down there? Tow ropes only cost a tenner or so, and if it's not too far then you can take it slow. Engine off, ignition on, so you can steer and indicate as needed. Brake plenty in advance because you won't have any servo assistance.
That's a good idea to be fair am sure I've got a tow rope knocking about in the shed somewhere. As you said just take it nice and slow and brake in plenty of time!
 

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Discussion Starter · #17 ·
I got the turbo changed last week over the weekend, we took the risk and drove it down to the mechanic it was smoking like hell but we made it. I feel a little sorry for the cyclist we drove past hopefully she forgives us lol. In the end i ordered a braided oil feedline and didn't bother reusing the oem one. The cars pulls so much better now and it accelerates nice and smooth too didn't realise how much of a difference it was going to make.

I was just trying to split apart the old turbo to have a look inside i wanted to see the extent of the damage but am having difficultly removing one of the 10mm bolts, am trying to get it off using a swan neck spanner but it keeps slipping anyone know of a better tool or the best way to get if off I think am gonna end up rounding out the bolt soon?
 

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If you keep at it with the spanner, rather than using sheer strength, try giving the spanner a few taps with a hammer to try and shock the bolt free. Much like an impact wrench would.
 

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Discussion Starter · #20 ·
If you keep at it with the spanner, rather than using sheer strength, try giving the spanner a few taps with a hammer to try and shock the bolt free. Much like an impact wrench would.
Good idea I'll definitely give that a go. I've noticed since fitting the second hand turbo there is slight whistling sound that comes from the turbo when you initially start to accelerate, once it gets going it disappears and there isn't any loss of power. I just wondered if this is normal or something i should look in to further? The only difference with this turbo is that it was broken from an estate and mines a hatchback but i checked with the buyer beforehand and the engine codes were the same. He didn't have the car mapped or anything. I'm not expert on turbos but i did check the turbo shaft on both sides and there was no shaft play and the VNT lever was moving nice and freely too.

I know you always take a risk when buying used turbos but couldn't afford a brand new one so second hand was the only option i just hope it's gonna last and this is not the start of something more serious.
 
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