Reasons for a slightly lumpy idle?

[iR8V10]

Only notice this when the car is idling, with the a/c on or off. The revs dip by a hundred or so every couple of seconds.

I had the MAF replaced as it was showing intermittent fault and there is no obvious misfire showing on vancom either.

Any ideas?

 

[s33nyboy12]

Vacuum leak possible, have a smoke test done at garage. Nearly all my hoses are silicone upgraded now.

 

[iR8V10]

Will get it tested, thanks!

 

[s3mad_dude]

Yeah mine is a bit lumpy too - maybe it's a noggy thing! Sometimes it's fine, other days just seems a little lumpy. I'll get it checked out when it's serviced. I don't think it's anything to "worry" about, but it certainly is annoying.

 

[iR8V10]

It's just one of those niggles... Like my perished radio antenna base. Going to get that sorted too!

 

[s33nyboy12]

Annoying........ Try having an over rev each time you change gear and 2 specialists ant solve it for love or money! That's annoying lol

 

[Paradox1]

Annoying........ Try having an over rev each time you change gear and 2 specialists ant solve it for love or money! That's annoying lol

That could be your clutch sensor btw

 

[s3mad_dude]

Haha I had a perished radio base too (first job I did after replacing the S3 steering wheel badge the day I picked it up!). Phoned Audi and they said they don't provide the part anymore but sold me the A6 base instead which is identical. You can get it on it's own (so you don't need to fork out for the mast too). It was about £10-15 iirc.

 

[iR8V10]

Good to know, thanks!

 

[s33nyboy12]

That could be your clutch sensor btw

Already replaced with new one, and tried scrappy one and it revs slightly up on let off accelerator not just clutch change......

 

[Paradox1]

Do you have a splitter valve or an atmospheric one?also do you have a catch tank? If so make sure the drain screw is tight

 

[s33nyboy12]

Do you have a splitter valve or an atmospheric one?also do you have a catch tank? If so make sure the drain screw is tight

I have forge 007 mate and no catch can, standard pcv system apart from bits of silicone and new hockey puck. Are we onto something boss? Hope you can help me lol