Hey all, im new here and I own a 2005 Polo GT TDi (VRS with a VW badge) and after 82000 miles the turbo shaft snapped, I replaced the turbo with a brand new one and within a month there was play in the shaft causing it to squeel/ whine on boost so I returned it under warranty to be told that is was caused by the turbo overspeeding! I believe this can be caused by some sort of leak from any of several pipes but I don't really know where to start. The EGR valve is leaking oil from the small breather hole, I wiped it away and within 250 miles it was back again so wether this is part of the problem I don't know. The other thing is the black box above the front drivers suspension strut wuth the pipes leading to it 'buzzes' for about 8 seconds after switching ignition off...is that normal or could that also be a contributing factor?

Haha sorry there is a bit of an essay there but kind of couldn't stop once I'd got going

Edited 12 May, 201115 yr by PoloGTTDi

Generally when a turbo overspeeds it damages the compressor blades.....not the shaft and bearings.

As both the problems you're turbos have suffered relate to either the shaft or bearings the most likely problem will be an oil supply, drain or oil quality issue.

Turbo overspeed damage to the compressor blades is often found on remaped engines were a turbo had been operated at the upper limits of the compressor map in order to achieve increased boost pressure.

HTH

Bill.

Edited 12 May, 201115 yr by vrs180

if you want to check for boost leaks, follow the pipe going into the egr backwards, checking all the connections as you go, through the intercooler, get the torch and shine down to the bottom one where most people have problems.

I checked mine for leaks yesterday just out of curiosity and found some traces of oil around the lower rubber pipe, just enough to collect on and run down my finger tips....should i be worried ?

Edited 12 May, 201115 yr by MarkMac

Pretty much each joint i have has oil around them :S only a bit but the joint does move up and down, and i had a shaft snap :(

Mark by lower rubber hose do you mean the one going into the bottom, of the intercooler? If so there will be more oil there than anyone, as this is the joint where most problems lie, also depending on, milage on car intercooler may.need drained of oil as this would cause the oil around the pipes. I dont have oil seaping at any of mine had some going into cooler but drained cooler and fitted oil catch tank and it stays nice.and clean now

Azza if the pipes are moving in and out the flanges will be worn,.get some cable ties on

Thanks for the replies. I've put duct tape around all the joints of the IC/Turbo hoses just to ensure no air is escaping and I've checked all the small pipes that run to and from the turbo and can't see any leaks. Just to confirm my car is standard so no remap etc which is why I don't understand the overspeed plus It has an oil and filter change every 6000 miles with VW recommended oil (a bit overkill but I was trying to prevent the problem I have now). My biggest problem now though is I don't want to fit my new turbo if its only going to be destroyed by the same problem :'(

Does anybody else have the buzzing black box when they turn their ignition off after driving/idling for a while? Because as that box controls all the breather pipes going to and from the turbo Im wondering if it might be causing some sort of problem?

Edited 12 May, 201115 yr by PoloGTTDi

Youd be maybe better off with cable ties as they work a treat! And I dont have the buzzing, altho.it buzzes intermitantly when the.engine is going and bonnet is popped, cnt hear.it otherwise. Have you had the car fault scanned? If all seems ok and no faults then it could just be pure chance that it happened again, could have.been a faulty part or anything. If its a geniune vw.part id have thought that there may be a years manufactureres warranty?

Ps how do I check the pipes connecting to and from the turbo itself? Or did you just mean the boost.pipes?

Ps how do I check the pipes connecting to and from the turbo itself? Or did you just mean the boost.pipes?

I meant the thin pipes that all lead to that black box, checked all seven of them, one goes to the wastegate and one to the egr and the rest seem to lead off to the engine. Just visually checked them for leaks but havent leak tested them. As for scanning the ecu for faults I ordered a VAG fault code reader last night so when it comes I will check it before I bother to refit the turbo. Also the turbo is from Turbo Solutions, bought a brand new one from them and it came with a 12 month warranty but it has just come back repaired under the warranty due to it only lasting a few weeks. It was them that told me it had oversped and to check for leaks, basically saying if it goes again we aren't covering it

I swear on blt engines that vacuum module buzzes after u turn it off? :S I cud be wrong lol

I meant the thin pipes that all lead to that black box, checked all seven of them, one goes to the wastegate and one to the egr and the rest seem to lead off to the engine. Just visually checked them for leaks but havent leak tested them. As for scanning the ecu for faults I ordered a VAG fault code reader last night so when it comes I will check it before I bother to refit the turbo. Also the turbo is from Turbo Solutions, bought a brand new one from them and it came with a 12 month warranty but it has just come back repaired under the warranty due to it only lasting a few weeks. It was them that told me it had oversped and to check for leaks, basically saying if it goes again we aren't covering it

fingers crossed for ya mate

Mark by lower rubber hose do you mean the one going into the bottom, of the intercooler? If so there will be more oil there than anyone, as this is the joint where most problems lie, also depending on, milage on car intercooler may.need drained of oil as this would cause the oil around the pipes. I dont have oil seaping at any of mine had some going into cooler but drained cooler and fitted oil catch tank and it stays nice.and clean now

its around this area of the pipe ive circled [almost hidden from view by the fuel filter piping] she's done 73k now !

p.s the image has been borrowed from google

cheers MM

Oil supply issue!

Did you replace turbo oil feed pipe?

Are you running the correct oil?

i havent changed anything yet? do these get blocked over time then? always run millers xfe-pd 5w 40 of cause

Edited 13 May, 201115 yr by MarkMac

Has it even been reconnected? Not the first time ive heard of that, would explain the very shory lifespan. Give the pipe a good clean and fit some.cable ties nice and tight and see if it solves it.

Oil supply issue!

Did you replace turbo oil feed pipe?

Are you running the correct oil?

No I didn't replace the feed pipe but did remove it and clean it out with carb cleaner and blew it through with an air pipe. The oil is 5w40 to vw spec so It's the right oil. I'll wait and see what the scanner picks up on if anything. Thanks for everyones advice, much appreciated

a

Edited 13 May, 201115 yr by PoloGTTDi

Has it even been reconnected? Not the first time ive heard of that, would explain the very shory lifespan. Give the pipe a good clean and fit some.cable ties nice and tight and see if it solves it.

Lol yeah I did refit it mate, checked and double checked everything before I started it up for the first time. I'll cable tie the IC pipes, scan the ecu and go from there with everything crossed

Thanks for your help mate!

Is the car remapped or running a decat?

It might have been mapped by a numpty

Oil supply issue!

Did you replace turbo oil feed pipe?

Are you running the correct oil?

oops thought you was asking me.... my fault for jumping into someone elses thread i guess

Is the car remapped or running a decat?

It might have been mapped by a numpty

Hi mate, no its not remapped, nor even has an induction kit, completely standard.

Just to let everyone know, I scanned the ECU this morning for fault codes and it only brought up one: code 17056 - Cylinder 2 glow plug circuit electrical fault. Which I'm guessing is a duff glow plug so will change that and see if the code reappears. But I can't see that having any effect on the turbo...unfortunately lol

Did you give the turbo a good run in period for all the bearings etc to loosen up themselves? Ie not driving to hard for 500 to 1000 miles? Doubt this caused it either but will def help in the long run. Im starting to think its pure chance, no related codes, no leaks everything is as it shud, id start thinking about quality of turbo?

Did you give the turbo a good run in period for all the bearings etc to loosen up themselves? Ie not driving to hard for 500 to 1000 miles? Doubt this caused it either but will def help in the long run. Im starting to think its pure chance, no related codes, no leaks everything is as it shud, id start thinking about quality of turbo?