Misfire when cold, which breather?

[museumsteve]

Bit of a newbie question. I did lots of searching and reading but ended up pretty confused so thought I'd just ask.
When I start up first thing in the morning the car seems to be missing for the first few minutes at which time it settles and is fine. I read lots of threads after searching but most threads ended up talking about possible split breather pipes. The problem is I took the engine cover off today and all I saw was a myriad of hoses and pipes so can someone give me an idea of the most likely culprit, or at least a place to start.
It's a 2001 MKi Leon Cupra.

Also I fancy getting it serviced fairly quickly and see theres no Haynes manual but that the MK4 Golf manual is very close, would the Golf manual cover the 1.8 20V T engine?

 

[adam cupra 20vt]

Sounds like the secondary air injection pump to me? its normal if it is.

 

[museumsteve]

Thanks for replying mate at least that's somewhere to start looking. Is it accessible/visible from the top (under engine cover)

 

[adam cupra 20vt]

Do you mean when you start it up from cold the car sounds a bit like a jet engine and revs quite high then after about 2 mins the revs calm down and it idles normally?

If so there is nothing to check as its the SAI pump pumping cold air into the system to reduce emmisions.........and this is surposed to happen.

 

[museumsteve]

No, when start from cold it drops revs every few seconds, more like a misfire. If I try and drive it it feels like it will stall. If I wait for say 30 secs/1 min then it settles and is fine

 

[adam cupra 20vt]

I'm not sure then.

On mine I always wait until the pump has cut out before i start driving.......although when the pump is running it does idle erratically.

 

[museumsteve]

Thanks for the replies mate
When I was searching on here alot of posts ended up along the lines of possibly faulty MAF or split breathers, just didn;t know where to start really

 

[traumapat]

Dirty throttle body?

 

[adam cupra 20vt]

The most common breathers to fail are the ones under the inlet manifold and the oil breathers coming from the side of the rocker cover

 

[traumapat]

No, when start from cold it drops revs every few seconds, more like a misfire. If I try and drive it it feels like it will stall. If I wait for say 30 secs/1 min then it settles and is fine

the rev needle swaying back and forth consistantly? +/- 200rpm ish?

 

[museumsteve]

I just started it (first time today). It starts fine and ticks over approx 1200 then after about 30secs/1 min the issue starts. It seems to 'spit' every few seconds, doesn't last long only maybe a minute'ish. The revs dont drop a lot, maybe drop to 1100 so not very noticeable but the spitting is noticeable.