Trouble?

[steamship]

Originally Posted by HPsauce

I looked earlier but didn't see one, sure you got the right thing?
I can only see one in the USA for about $200.

Yes, the code that Jim listed is the same as the one I posted in post #17. I just remove the spaces when doing a search for it. Only thing to ensure is that it is a BD one, which is for petrol, and not the BC one for diesel.

[HPsauce]

As I may have mentioned elsewhere the knocking noises (loud!) are the catalyst, and it needs doing PDQ.
The hesitancy symptoms have got worse in recent days so I'll get the catalyst fixed first to see whether or not it's a factor.

I have also acquired a throttle pedal sender potentiometer (from our sponsors of course ) but will hold off on fitting that for now.
There are references online suggesting that the throttle BODY needs recalibrating (I have done that before while investigating this) after changing the pedal or sender (not 100% sure why) but is there any need or method for calibrating the actual sender on the throttle pedal (I can find nothing about that) or is it effectively "preset" at manufacture?

[brasiliangringo]

I drove my S8 without the OS cat for a few months. Wont hurt anything other than emissions. It was only when i changed it did i realise quite how bad it was - it was hollow, over time blew the monolith out the rear.

[HPsauce]

It could depend on age; mine is the later type with post-cat lambda sensors and I guess the readings from those "might" have an effect.
Either way, I normally follow the "only change one thing at a time" philosophy when trying to resolve problems.

[Adrian E]

If you change anything to do with the throttle control, turn the ignition on for 6 seconds before starting. In theory this will check if a basic setting is required (after a battery change or replacement of parts) and do it. There's no obvious sign it's been done, so the manual process with VCDS does give some confirmation that all values are in range.

[brasiliangringo]

Originally Posted by HPsauce

It could depend on age; mine is the later type with post-cat lambda sensors and I guess the readings from those "might" have an effect.
Either way, I normally follow the "only change one thing at a time" philosophy when trying to resolve problems.

Mine was an 02 - yes it threw an post cat emmision code but doesnt hurt anything.

[The_Laird]

Damn - the problem is back again, less than a year after fitting a new throttle position sensor.

Exactly the same symptoms and, yet again, towards the end of a 30 mile drive in heavy rain.

But then after standing at work, no problems on the way home or the next day.

I'm more convinced it's a leak and my local Audi indy says there is a leak, but on the n/s, but that all the drains are clear - Botang's hole perhaps?

So, if it is Botang's hole leaking, could water find the throttle position sensor, or associated electrics?

It's going back in a week or so for a more thorough investigation (so pray for a dry spell as I need the car for a couple of key trips!), so I'll update this when I know more.