Fault code 49508

[maxpayne]

The other day when driving back on the M1 I noticed that I had to press the accelerator a lot to increase speed. Almost felt like the car had lost any capability to boost and wouldn’t rev beyond 2000 RPM even.

I should mention that this happened after being on cruise control for most of the journey and I even used the speed +- option to increase decrease the speed with no problem.

After we came home I used Carisata (sadly no VCDS at home) and it displayed fault 49508 - a fault that seems to be non existent apart from some random Mexican forum where someone was pointing to issues with the DV valve!

Any ideas anyone?

Thanks!

 

[audismart]

If that code came from your VCDS cable then give Gendan an email mate, they will put you right in the link below.
http://www.gendan.co.uk/

 

[maxpayne]

If that code came from your VCDS cable then give Gendan an email mate, they will put you right in the link below.
http://www.gendan.co.uk/

I have a basic wireless ODB diagnostic dongle. In retrospect should have got a 10 VIN VCDS cable since I’ve already spent £60 coding various things!

 

[audismart]

Which varient do you have mate, S3 or A3 k04 or k03 turbo, S3 has k04 turbo and the DV valve sits at top of engine and easy to check, K03 sits at bottom of engine and is a pain to get to but doable for a DIY. pull the DV and look for a split in the diaphragm.

 

[maxpayne]

Which varient do you have mate, S3 or A3 k04 or k03 turbo, S3 has k04 turbo and the DV valve sits at top of engine and easy to check, K03 sits at bottom of engine and is a pain to get to but doable for a DIY. pull the DV and look for a split in the diaphragm.

I have an A3 2.0T - I believe the DV sits at the bottom? Coincidentally the car is at Audi (Finchley Road) today for MOT but I bet those guys will charge a fortune to check for the DV!

Maybe I should get the G rev (I think D is the newer version but G should be good enough for a 2.0T and holds the boost better and hopefully not split) and get it installed by a local mechanic...

 

[audismart]

Get a GFB DV+ fit and forget, you'll never blow another one.

 

[ch1z64]

The other day when driving back on the M1 I noticed that I had to press the accelerator a lot to increase speed. Almost felt like the car had lost any capability to boost and wouldn’t rev beyond 2000 RPM even.

I should mention that this happened after being on cruise control for most of the journey and I even used the speed +- option to increase decrease the speed with no problem.

After we came home I used Carisata (sadly no VCDS at home) and it displayed fault 49508 - a fault that seems to be non existent apart from some random Mexican forum where someone was pointing to issues with the DV valve!

Any ideas anyone?

Thanks!

Now you sure your fault code never started with a zero making it 049508

 

[Nessy]

The other day when driving back on the M1 I noticed that I had to press the accelerator a lot to increase speed. Almost felt like the car had lost any capability to boost and wouldn’t rev beyond 2000 RPM even.


Any ideas anyone?

Thanks!

I don’t know what engine you have and given that you’ve mentioned a dump valve I guess it’s not a diesel but I had a similar symptom once on my TDI after I’d replaced a few of the sealing rings on the intercooler pipework and hadn’t properly got the locking circlips which hold the pipes together to seat properly (unbeknown to me).
One of the joints popped apart on boost and the car ran like a dog until I could get it home and underneath the engine to properly re-set the pipework joint.
Car was flat out at 50mph and had no turbo boost whatsoever.

 

[maxpayne]

I don’t know what engine you have and given that you’ve mentioned a dump valve I guess it’s not a diesel but I had a similar symptom once on my TDI after I’d replaced a few of the sealing rings on the intercooler pipework and hadn’t properly got the locking circlips which hold the pipes together to seat properly (unbeknown to me).
One of the joints popped apart on boost and the car ran like a dog until I could get it home and underneath the engine to properly re-set the pipework joint.
Car was flat out at 50mph and had no turbo boost whatsoever.

I have a 2005 2.0T with engine code BWA.
Drove the car to Audi to get MOT (passed with no advisory yay), DSG oil and brake fluid change (all were due) and seems that things have improved a lot since day before yesterday when I witnessed the problem.

Was tempted to ask Audi to investigate but the stealership labour costs are too damn high. Need to find a good indie nearby!

 

[Nessy]

I have a 2005 2.0T with engine code BWA.
Drove the car to Audi to get MOT (passed with no advisory yay), DSG oil and brake fluid change (all were due) and seems that things have improved a lot since day before yesterday when I witnessed the problem.

Was tempted to ask Audi to investigate but the stealership labour costs are too damn high. Need to find a good indie nearby!

I’m sorry I’ve just remembered that’s only half the story......!
The full story is that I renewed a few of the intercooler seals one day and the next day going to work I gave the car some serious welly coming off a roundabout .
Cue a loud bang and the car ran like a dog, hiccuping and generally no performance at all.
As I was on the way to work I limped the final mile there but couldn’t do much more until I’d finished my shift and had to get the 40 miles home.
By now it was late and dark (9pm) so I called out the RAC and he was stumped as to what it was but he found that if he disconnected the MAF sensor it at least stopped juddering ,albeit with no performance or turbo boost.
This at least made the car driveable enough to make a very slow journey home along the motorway at a max 50mph!
It was only the next day, in daylight that I could see the popped apart intercooler pipe that had caused the bang.
Once the pipe had been re-seated and the MAF sensor connected again the performance was back to normal.
So I’m going to revise my diagnosis and say it’s MAF-related and not the intercooler pipes!

 

[maxpayne]

Update. Was due to fit new PCV, DV valve and cam follower but the darn parts didn’t arrive in time!

In the meantime I had reset all fault codes and did a scan today and nothing.

However on our way back from shopping, I once again felt the loss of boost

Did a scan after coming home and nothing. However I noticed something interesting:

The engine was reving at 900 at idle. Pretty sure normally it revs at 1100. Mystery continues...


Sent from my iPhone using Tapatalk

 

[audismart]

Standard warm idle with the heater on is 800rpm heatewr off and it drops off slightly and 1100rpm when cold, your pcv will sort that and the boost issue will be improved with the dv.