Golf GT TDI - Loses power but motor keep running??

[buckworld69]

I am trying to resolve an intermittent technical problem that seems to be a common theme on forums but VW don't seem to be able to help. Whilst driving, the car just loses all power but keeps on running. No matter if I gear down or try accelerate the car just keep on plodding along at about 40-50mph which gives to time to pull over. When the car is turned off and on it fault seems to reset and the car tears off again. It may not happen for 50 miles or may happen 5 times in a mile, no matter if driving in town or the motorway. To make matters worse I found out the car is clocked too.

VW replaced the Air Mass Meter but the fault continued, so they then suggested the next option is to replace the turbo at £1800. Clearly their pockets are deeper than mine. Even though my knowledge of engines is dangerous even I can guess that a fault with the turbo would not be fixed by turning the car off and on. This makes me think that it must be faulty sensor or the engine management system that corrects when the power is cut with the ignition.

I had the car looked at by another garage who also could not locate the fault but got fault messages suggesting that it could be losing pressure through cracked hoses. All were inspected and found to be in good order.

I found some American forums that were suggesting that their similar fault could have been solved by replacing the O2 sensor, or turbo regulation solenoid. Has anyone else come across this and solved it, or have some advice that could try convince me that replacing the turbo would likely solve the fault. I've already lost loads of value in the car due to the clocking so am loathed to systematically replace engine parts while VW guess their way to the fault.

Hope someone out there can help me out.
Thanks,
Buck

[RickT]

Hello and Welcome to the forum!!

[troublemaker]

well it could be the turbo - but i would say that it is unlikely to be that unless there are other symptoms.

lets get some more data - first off how many miles is it reading, and how many has it done?

[troublemaker]

oh..........and err..............bit cheaper than £1800....

http://cgi.ebay.co.uk/TURBO-UNIT-DIE...QQcmdZViewItem

you should be able to source a full unit recon for £400 nowadays comfortably for most vehicles

[Huweth]

Have you looked at the vane actuator on the turbo? It adjusts the vanes to provide the right boost depending on RPM and loads. If it is sticking (common) the ECU will register overboost and the car goes into 'limp mode' until you restart it.
It will look somthing like this on the turbo.

You need to make sure the little rod inside is moving freely. Give it a good push/pull to free it if stuck. Soot deposits on it and it sticks. After that, give the car a good blast and get the turbo REAL hot to clear the gunk. These turbos must be pushed regularly to prevent sooting. I drive mine hard each day up the same slip road and haven't had any soot buildup.
If this is your problem, you will notice a difference straight away.
Good luck and let us know how it goes.

[buckworld69]

Hi all,

Thanks for all your feedback. I myself am not very clever under the bonnet so will have to have someone take a look for me with your comments on board.

On the clocking front, its on 37k now but have a feeling it's more like 130k from info I have investigated. No thanks to Trading Standards though!! I have had a health check and an MOT done on the car and it passed all OK otherwise, so was looked after well by whoever the fleet company was that had it before me.

The 'limp mode' is a very apt word to describe how the car feels when it loses power. I would appreciate some more tips on what it might be so that I can give the mechanic looking at it for me some more info. He's got all the monitoring equipment required for the car, but without the heavy labour rates.

On the recon turbo front, I heard that they are coded and VW will charge a heavy fee to hand over the code. Any truth in that?

Thanks for all your help,
Buck

[Eshrules]

Hi all,

Thanks for all your feedback. I myself am not very clever under the bonnet so will have to have someone take a look for me with your comments on board.

On the clocking front, its on 37k now but have a feeling it's more like 130k from info I have investigated. No thanks to Trading Standards though!! I have had a health check and an MOT done on the car and it passed all OK otherwise, so was looked after well by whoever the fleet company was that had it before me.

The 'limp mode' is a very apt word to describe how the car feels when it loses power. I would appreciate some more tips on what it might be so that I can give the mechanic looking at it for me some more info. He's got all the monitoring equipment required for the car, but without the heavy labour rates.

On the recon turbo front, I heard that they are coded and VW will charge a heavy fee to hand over the code. Any truth in that?

Thanks for all your help,
Buck

i think huweth more or less hit the nail on the head TBH. on the turbo front, pardon my french but ******, no, VW dont code their turbos not sure who told you that, but its a bolt on bolt off part, only when your coding keys and ecus etc do you need codes and alike.

just a tip, as per the sticky thread, try posting this in the golf section, this post will tend to get missed as its in the new member section

[troublemaker]

On the recon turbo front, I heard that they are coded and VW will charge a heavy fee to hand over the code. Any truth in that?

Buck. If the car was bought from a motor dealer you have a path of recourse over and above a private seller milage wise - anyway moving on, more importantly you need to consider what a turbocharger is to understand there is no "mystique" to it.

Its simply an air pump, driven by exhaust gas. Exhaust gas flows through the inner chamber of it, spinning it, and on the outside chamber (they both use the same turbine.....) intake air is pumped through.

As already mentioned - its normally only electronic components which need "coding" to the given car. A common one is the ECU to the transponder in the key.

[buckworld69]

Thanks to all for the further advice, please keep it coming so that I might finally sort this car out.

How would I move this thread to the Golf section of the forum? Or do I have to start a new one?

Thanks,
Buck

[devonutopia]

Tried the boost sensor too? That can also throw the car in to limp mode - It did with me. I'll try and move the thread. Yay! My first thread move. Hope it gets you more response.