Turbo Only Working On Cold Mornings!

[Jazzman]

I have had a long standing fault with my turbo on my Y reg 1.9 15bhp galaxy, namely no turbo! It will come back on momentarily if I reset the ignition whilst driving but as a rule, I struggle around without any turbo assistance. I have noticed that on these colder mornings doing the school run, I have turbo, but not for long. Has anyone else had this problem? My local garage has a replacement pipe on order, (not sure I need it?), is there a temperature sensor that could be faulty? Many thanks in advance for any replies! Jon Edited October 22, 2008 by Jazzman

[insider]

The symptoms sound like it's going into "limp home" mode for which there are numerous posts on the forum. It's basically due to the variable nozzle mechanism not working properly which could be because of blocked or leaking vacuum pipes, faulty actuators or just a sticky mechanism. Search the forum and you'll probably find the answer.

[Jazzman]

Thanks for the reply. I have researched just about all the turbo-related posts on the site & I know it's going into limp mode. I really would like some specific advice about how temperature, (in my case-COLD) affects the function of the turbo. THANKS Edited October 22, 2008 by Jazzman

[insider]

Possibly because cold air is denser, less turbo boost is required so you are less likely to over-boost and go into limp mode.

However, this doesn't solve the obvious fault you have with the turbo, etc.!

[f0ster]

if the system is reset by switching off the ignition and back on, do you get boost for a short while, if it works for a short while then goes back in to limp home it will be because the boost pressure has gone too high which is picked up by the pcm and puts the system in to limp home, most likely turbo vanes sticking,

there are other causes, the boost pressure control pipes can become blocked with oil preventing the air from getting to where it should, I would start with the cheap stuff, pipes and n75 valve (n75 controls the boost) unless you can find something obvious.

[Triple Trouble]

I have had a long standing fault with my turbo on my Y reg 1.9 15bhp galaxy, namely no turbo

 

Blimey I did not realise without the turbo the power was so low! :rolleyes:

 

 

 

 

Sorry could not resist - hope you get it fixed soon, and cheaply!

Edited October 22, 2008 by Triple Trouble

[Mirez]

Possibly also because metal expands at temperatures. The colder it is - theoretically at least, the more room the vanes would have to move - albeit only a tiny difference.

[insider]

Possibly also because metal expands at temperatures. The colder it is - theoretically at least, the more room the vanes would have to move - albeit only a tiny difference.

If you're suggesting the vanes have more room to move because they contract when it's cold, then surely the surrounding metalwork of the turbo would contract by a similar amount, rendering the clearance the same?

[Mirez]

I'm saying its a possibility, a theory at the least. Without knowing the exact metals in use, the densities, the structure and the clearances you couldn't possibly make any exact statements here but again in theory, the vanes are likely to be significantly thinner then the case metal.

[Scorpiorefugee]

I don't want to send you off in a wrong direction but I have to ask if you are sure that it is the turbo. The reason I ask is that I have an intermittent loss of power which is very severe, albeit on the 110 AFN engine and, in spite of he fact that it is common practice to blame the turbo for this sort of problem, I am certain that the problem has nothing to do with the turbo. The clue for this is that the repeating fault code is 550 - Injection timing.

 

I have had a look through your posts and cannot see anywhere you have checked the fault codes although I may have missed it. I recommend that you invest in a VAG com for about

[insider]

I agree that investing in VAG-COM would be a good idea.

 

However, as Jazzman has a PD engine (115bhp) this will not be a timing problem. The timing on PD engines is set when the timing belt is locked in position and then controlled by the ECU. It cannot "drift" in the same way as a TDI since there is no needle lift sensor. Incorrect timing on a PD engine would be a constant problem, not intermittent.

[seatkid]

As insider said - Check the vacuum pipes for splits, dodgy connections, blockages. If in doubt - change the pipe. Then check the turbo actuator moves freely (there is a thread describing how to check, lubricate and free it up). These account for 90% of limp home problems.

 

The "works when cold" could be anything - pipes shrinking, turbo clearances changing, sensor readings drifting. You shouldnt read anything too significant into it.

[raashid]

Hello there

just to give you a hint here. i have Galxy 2004 TDI auto and was having a same problem. Someone suggested to change the MFI hwich is fitted on the air filter Box. I checked the price and it came to thearound

[Jazzman]

Your replies have been really helpful, many thanks, please feel free to contribute to what is becoming a lively & interesting thread. Jon :lol:

[Jazzman]

Fixed!!!! my local garage changed a pipe which they said was split, and replaced the MAF sensor-I think it was just the pipe that was needed as I replaced the MAF about a year ago , so I have a spare MAF for sale!----car runs absolutelly A1, thanks again for all thoases replies that were helpful!

[Desmond]

I also had this problem aparrently it was a pipe going into one of the radiator doohickeys at the front of the car pipe replaced turbo works ok for over 12 months now