Poor running on cold start. Ideas?

[andrew_lumb]

Hey,

My vRS generally runs fine, and I love it to bits! but maybe 2 or 3 times a week when I start it from cold, it struggles to run/idle. It sounds to be running on 3 or less cylinders, but once I have manouvered off the drive, and pulled away, it rights itself and the car drives ok.

I'm looking for ideas as to what the cause might be. I can't take it to skoda, because the engine is warm by the time I get there, and it doesn't replicate the problem!

So, what could it be?

(Coincidently, I just spotted that the breather hose is split from the cam cover to the inlet manifold - I have a new one on order, but might this be related to the misfire-like running problem?)

Cheers,

Andrew.

[andrew_lumb]

A bit of research on here turns up Coil Packs.

Are these symptoms correct for a coil pack that is on it's way out?

I plan to start modifying the car soon (panel filter, forge 007p, cat back exhaust, remap, etc) and would like to make sure it is running in top condition first.

?

[Taxi 219]

Loads of stuff relating to this if you use the "Search" facility.Iam sure all your answers will be found:thumbup:

[phillip]

If it was the coil packs the problem would be there permanently and the engine management light would be on...it would not clear itself when warm. Anyone any other ideas :confused:

[jimmyskeen]

Normally its the cold start air pump that causes ther car to struggle from cold start up as it pumps air into the cat - mine had got quite bad over the past month or so along with some other low rev running faults - i changed the air temperature sensor that sits in the inlet manifold just after the throttle housing - held in by a 5mil alen key bolt & 1 multiplug cost around £ 26 - did the job for me, been on for about 1 week car is running spot on

[martziniuk]

Possibly the secondary air pump. You can hear it blowing away for around a minute when cold started, if it runs better after this then its prob your pump leaking.

[andrew_lumb]

I'll have a listen for the air pump tomorrow, and go from there.

The management light does not come on - does this indicate that the sensors are all working fine?

[mattbeef]

No as when i had a coil pack go i never had the CEL come on but knew it was a coil pack

[Bodge]

mines done this twice now.

why would the air pump leaking effect the running of the engine?? the pump just pumps fresh air down the exhaust manifold to give the cat more oxygen on cold startup surely.

someone on here has a completely broken air pump and his car runs fine. i thought it was purely an emissions helper.

think it's just got cold and there's not anough juice getting to the coils while the pump is still running and at low revs.

dunno.... just wait till it warms.

i feel i have been useless.....!

[andrew_lumb]

yeah, if i give mine a few revs, it's okay, but when it drops back to idle, it starts hunting again.

my new breather pipes come tomorrow, so i'll fit them. i'll change the plugs too (cheap), and i'm gonna buy a new recirc valve, because that is a bit suspect too.

cheers for the pointers

[9000rpm]

I've just got my VRS and it had the same problem this morning. it been remapped by jabbasport and I'm wondering if its the standard DV failing or something else so please report back if you find out what it is of if the new DV helps.

[jimmyskeen]

The DV would NOT effect the running at idle speed so rule that straight out

[Richy Fitt]

Mine has same problem and I usually only get it when the temp overnight has dropped below 3.5C. I usually turn engine off, restart and it is usually ok. If not i wait about a minute and hey presto it runs perfect.

[AwesomeSarah]

Coolant temp sensor Very common fault

These will make the engine think it is warm when it is cold and cold when it is warm

Wortha try at only £25 ish

Sarah

[RichB86]

my secondary air pump is dead and i get this on very cold mornings and usually spot it by the car idling slightly higher so a quick restart before driving off and it seems to sort itself out.

i was told that the pump was just to get the car through emissions tests when cold.

i also read it can be the MAF disliking the cold.

[andrew_lumb]

Regards the CTS..

It appears to work - holds 90deg when warmed up - so is it just out of range at cold temperatures?

[yellerRs]

Mine used to run terrible from cold, as you say sounded like it was on 3 cylinders!!

I cleaned the MAF and the problem has gone, not sure that this will affect it or whether it was a coincidence!

Benn fine, touch wood for a couple of months now!

[andrew_lumb]

Well, I changed the y-shaped breather hose on the top of the engine, because this was split. Perhaps it was taking in unmetered air? While I was there I also loosened off all the intake pipes, jigged them about a bit, and refitted - just to make sure they are all seated correctly.

The problem hasn't returned since, so touchwood it is okay now.

New recirc valve on order now too..

[KenONeill]

A split breather is often a cause of poor running.

[andrew_lumb]

Well, it hasn't misbehaved again since changing the pipe..

Then it hasn't been excessivley cold out either, so I can't rule out temperature yet.

CTS appears to be functioning correctly too.

[jesters3]

Agree with AwesomeSarah. Had the same fault on the S3. Did the usual (MAF, clean TB, coilpacks, hoses etc) and it sorted itself out after I changed the temp sender.

[andrew_lumb]

This will be my next port of call then, if/when it does it again.

Cheers for everyones input

[vwnutant]

just got my auq 2001 y reg

mapped by jabbasport

full stainless from turbo

baileys dv

jabba induction kit

adjustable boost valve

mine seems to hunt all over when cold , and jumps like a broncho for a mile or two but is then fine

it also seemed to have a lack of power today when on mway , and then turned off and on again it was fine ? ....

going into awesome gti next week for a full check up ...

what things from the list are best to check/change ?

ant

[vwnutant]

Okay changed my d/v to one similar to a forge one

ordered a new breather pipe

and next on my list is-

Coolant temp sensor

Intake air temp sensor

plugs

clean throttle body

I already have no secondary pump so cant be that.....

will report back once done ....