lumpy cold start??

[Joel_vRS]

more notciable in the morning when the air is cooler will start car and untill driven will idle very lumpy as if its going to stall

any ideas?

Thanks

Joel

[gibbo01]

You got an after market air filter ie Carbonio on it?

[Tech1e]

The throttle valve may need resetting (requires VAG COm or diag tools).

Or possible coolant temp sensor.

[jason]

i had this today in my vrs octavia,thought it may be me not being used to the fly by wire throttle,i stalled it today when cold starting,sounds a bit lumpy when cold.

would realigning the throttle body help?i take it its the same as the rest of the 20vt range,dissconnect battery etc etc

[SkodiRS]

Did you guys just start and go or did you wait until the idle settled down to around 800rpm?

If you just started and went then this is normal...I think it's the VVT sorting itself out......

My normal disclaimers apply.

[Joel_vRS]

i do have a K&N air filter and thought that may be the root of the problem...

not sat there and waited for it to settle down idles just over 1k lumpy as if the car is too much choke on... After its been run and is up to temp ie choke disengaed its fine..after reading this i think it might be the VVT..

Joel

[jason]

does it have vvt?

[ecklad]

Mine does this, It has stalled twice... But it does not matter if I leave it for approx 20sec or drive away straight off,, it still requires more revs than normal.. Dealer has got a potential cure on the Skoda information Database.

It talks about replacing a pipe in the induction system.....

?? I'm considering getting it done..

Question.. Why would it only happen when its stone cold? What in the VVT

arrangement need sorting?

Bad running in cold start situations are usually caused by the failure etc of the fuel richening systems....

Cheers

Dazz

[SkodiRS]

does it have vvt?

Yep but not for performance.....just emissions...IIRC.

[jason]

but surely vvt would only come in at high rpm,i'm talking tick over and part throttle,when mined stalled :confused:

[Smithy vRS]

It's just helping the engine warm up and run when cold, and i for 1 think the niose it makes wit the KnN is class only last 2mins on mine.

[SkodiRS]

but surely vvt would only come in at high rpm,i'm talking tick over and part throttle,when mined stalled :confused:

Where's Mike (KLB) when you need an explanation.

As far as I understood it the VVT on the 1.8T is not performance related.....I thought it was for emissions on start-up.....I'm sure Denis, Mike or anyone who knows can clarifiy.

[Joel_vRS]

It's just helping the engine warm up and run when cold, and i for 1 think the niose it makes wit the KnN is class only last 2mins on mine.

i must admit it does make the k&n roar for on that first start, so its nothing really to wory about but can be fixed if need be??

surely it will get worse tho as the winter approches to the point where a frosty stat will just keep stalling the car on first start up?

joel

[ecklad]

I must point out my 2 pervious 1.8T engines in my Leon's never suffered from this...

cheers

Dazz

[DGW]

There is a FAQ about VVT here which confirms Adrian's recollections of what it is for.

[SkodiRS]

There is a FAQ about VVT here[/url'] which confirms Adrian's recollections of what it is for.

:yeahdude: ...Cheers Denis!

[ecklad]

Ok.. VVT ... All three cars have had this engine.. So why is the Octy the only one affected?

cheers

Dazz

[Tech1e]

If you getting a noise within the first 2 mins of a cold start, maybe like a growling noise if you have a K+N I would have thought thats the secondary air injection and not anything VVT related. This pumps oxygen into the exhaust to lower emissions on cold start uip.

And if you have cold start problems and poor idle CHANGE YOUR COOLANT TEMP SENSOR like I said in my first reply. This is a well known fault with VAG engines and they are on about the 10th supersession for the sensor.

And no disconnecting your battery wont reset the throttle body, in fact its the loss of a 12v supply that causes it to loose it settings in the first place.

[jason]

cheers for the link,best get the cover off and find out .

what sort of price is one of the coolant temp sensors?is it DIY able?

thanks for the replies,

[Tech1e]

Piece of cake to change the temp sensor. It sits on the top coolant pipe just above the bellhousing of the gearbox, held in with a plastic horseshoe shaped clip.

I think they are about

[DGW]

If it's the dual temperature sender then it is (or was)

[jason]

cheers for the info,is it possible to be picked up by 1551(2,3 or what ever they are on now)save me gambling on which one it is?could it just be cacked up with crud and just need a clean?i'm a cheap skate at heart,new car and i may need to spend money on it,and all that,sorry for all the questions on this but the 20vt is bloody complex just looking to see what does what,

[jason]

Piece of cake to change the temp sensor. It sits on the top coolant pipe just above the bellhousing of the gearbox, held in with a plastic horseshoe shaped clip.

I think they are about