Help with VCDS. VAGCOM detectives needed!

stealthyspeeder

Hi all, after getting my gearbox completely refurbished I took the car to get a full diagnostic scan. The car is a 2003 Audi RS6 C5. Now the following codes are on the car, but I cant see them on

http://wiki.ross-tech.com/wiki/index.php?title=Category:Fault_Codes&from=16785%2FP0401%2F001025

17983 - (P1575)
18393 - (P1985)
18308 - (P1900)

My mechanic is going to look into these but he is really busy and cant look at it till next week, so thought I would do some investigating.

Now these are relatively minor, apart from the coolant control one, however the car is misfiring. The diagnostic is not picking it up either as a misfire count error code or through live misfire counting (0 misfires detected). The misfire is small, only noticeable with the air con and radio off and occurs throughout the rev range (ie not just idle and then out with a bit of gas).

So as pretty much everything in the engine bay came out for the gearbox, a possible cause could be a air/vacuum leak which would be consistent with the above.

So I would greatly appreciate any speculation on what could be the issue with the undetectable misfire could be as I see that as the most serious concern.

I would also appreciate any possible root causes for the above codes?

Thanks!

tossy

Was it scanned with a spurious scan tool Rik or VCDS? was there any text with the codes? with VCDS you get a line of text which pinpoints the faulty module and then the code which pinpoints (usually) the exact cause.

If your mechanic put the gear box back in and turned the car over to see if it was running smoothly and waited before reconnecting sensors not associated with gearbox then a raft of codes would be logged in the ECU.

If you want it scanned with VCDS (presuming it hasn't already been) then give me a shout.

Falling that some 4.2 wizz kid on one of the audi forums or Vwvortex.com might be able to help with the codes.

stealthyspeeder

tossy wrote: »

Was it scanned with a spurious scan tool Rik or VCDS? was there any text with the codes? with VCDS you get a line of text which pinpoints the faulty module and then the code which pinpoints (usually) the exact cause.

If your mechanic put the gear box back in and turned the car over to see if it was running smoothly and waited before reconnecting sensors not associated with gearbox then a raft of codes would be logged in the ECU.

If you want it scanned with VCDS (presuming it hasn't already been) then give me a shout.

Falling that some 4.2 wizz kid on one of the audi forums or Vwvortex.com might be able to help with the codes.

I should just pm u before making a thread lol, yea it was vcds and there was text althougth i just jotted down the codes.

The error codes are not my maina concern, apart from the coolant fan i think they are solved with straight part or sensor replacment. what does worry me is the undectable misfire! any ideas?

Will join up to that forum this eve!

tossy

I would have no idea Rik a blown coilpack would throw up a fault code and text.

Diagnosing a misfire,first i would determine the cylinder that is misfiring and go from there coil pack,plug and HT leads after that my expertise runs out!

pie-man

how do the fuel trims look? this will give a indication as to possibily problems with mixture correction. tbh if this had a genuine misfire it would be picked up by the management system. ive never seen one that wasnt. as regards your other codes the fact there is no description in the wiki and you didnt post the text i cant really comment. but if you or your mechanic run out of ideas id suggest going to someone with vas6150a of equivilant as one of these machines has guided fault finding for all the fault codes etc. also posting your engine code would help....me or others might know common faults on a particular engine etc

stealthyspeeder

Misfire completely cured with a fill up at maxol, now idling completely smooth!

Never buying fuel at topaz again.

-Corkie-

stealthyspeeder wrote: »

Misfire completely cured with a fill up at maxol, now idling completely smooth!

Never buying fuel at topaz again.

Who done the box after Stealthy??

stealthyspeeder

-Corkie- wrote: »

Who done the box after Stealthy??

Thanks for the contact by the way though I went with these guys in the end

http://www.burnsidegarage.co.uk/automatic_transmission_repairs

highly reccomend them, they are the longest autogearbox refurbishers in the whole of Ireland, and the price they quoted me was the price I paid. Anyone I phoned down south didnt want to know, ridiculous quotes, no quotes and I even got one guy say "An RS6?, done that before, never again"

They have done pretty much everything with an auto in it. They take their time with the cars and prefer to run them in themselves (I needed mine so was very gentle for the last 600 miles). Also had to wait a month before they could see me, they have that long a waiting list!

Gary ITR

stealthyspeeder wrote: »

Thanks for the contact by the way though I went with these guys in the end

http://www.burnsidegarage.co.uk/automatic_transmission_repairs

highly reccomend them, they are the longest autogearbox refurbishers in the whole of Ireland, and the price they quoted me was the price I paid. Anyone I phoned down south didnt want to know, ridiculous quotes, no quotes and I even got one guy say "An RS6?, done that before, never again"

They have done pretty much everything with an auto in it. They take their time with the cars and prefer to run them in themselves (I needed mine so was very gentle for the last 600 miles). Also had to wait a month before they could see me, they have that long a waiting list!

And they are far away!

stealthyspeeder

Onkle wrote: »

And they are far away!

Nothing a bit of vtec didnt sort out!

tossy

stealthyspeeder wrote: »

Nothing a bit of vtec didnt sort out!

Ive never done it now but i imagine getting into the RS6 after a vtec is akin to getting up on gisele bundchen after riding Mary Byrne from the X factor.

lomb

How much did it cost in the end Stealthy?
Nice car by the way.

Gary ITR

tossy wrote: »

Ive never done it now but i imagine getting into the RS6 after a vtec is akin to getting up on gisele bundchen after riding Mary Byrne from the X factor.

You did not just compare my car to Mary Byrne....

stealthyspeeder

tossy wrote: »

Ive never done it now but i imagine getting into the RS6 after a vtec is akin to getting up on gisele bundchen after riding Mary Byrne from the X factor.

lol

lomb wrote: »

How much did it cost in the end Stealthy?
Nice car by the way.

2,280 sterling all in (VAT, parts and labour)

Onkle wrote: »

You did not just compare my car to Mary Byrne....

Awh come on, Mary Byrne is a great singer!