Hello all,

 

I've had my MkII VRS 2.0 TFSI for a shade over 18 months now. Not long after i first bought the car i noticed that it could be quite hard to start on the first start of the day. Turning the key over it would cough and splutter and sound like it was going to stall before catching. This would typically only happen on the first start of the day and from then it would be fine. Once up and running the car is absolutely spot on and there are no fault codes logged anywhere in regard to the issue.

 

The problem seems to occur when the car has been left standing for a few hours (like after a 12 hour shift) and although it is exacerbated by cold weather - on a couple of occasions in winter it has stalled outright before firing up on the second turn of the key - it happens no matter what the weather conditions, it seems that the time the car has been stood is the causal factor.

 

Initially i attributed this to the battery probably being on its way out, however changing the battery made no difference and the issue persisted.

 

I've tried to following attempted fixes to no avail:

 

- New battery

- PCV Updated to latest revision

- Fuel Filter Replaced

- Cam follower changed - original had ~40k miles on it and was showing no real signs of wear

- Spark Plugs replaced

- Coil pack recall checked (has already been done prior to my purchasing the car)

- VCDS scan, no fault codes

 

I understand starting issues can be linked to a faulty drivers door micro switch causing the fuel lines not to prime when the drivers door is first opened, however i can hear the pump prime when i open it and all of the dome lights seem to be coming on as they should and the dashboard correctly displays when the door is open/closed so i don't think this is the problem.

 

I've read that turning the ignition key to the accessory position (electrical systems on) and waiting a few seconds before turning over the engine can prevent this problem, it does help but doesn't eliminate the issue. I've also been told this is just a 'normal' behaviour of these engines - i cant see that being the case given that every other modern car I've driven you can just get straight in and turn the engine over. 

 

The only 'solution' I've come up with is to blip the throttle when turning the key, this seems to help the engine catch first time.

 

Could the fuel system be losing pressure when stood overnight?

 

The way the car coughs and splutters like a chain smoker before nearly stalling and then catching is starting to get annoying and more than a bit embarrassing now, so any help or ideas will be greatly appreciated!

 

Cheers

Edited 14 September, 20169 yr by BigJakk

Could also be coolant temp sensor, Maf or tired battery. Recommend sensor first

I am fairly happy its not the battery. The new one i put in last year is above and beyond the power rating of the OEM battery, however to be doubly sure i went out and checked with the multi meter last night.

 

Car had been stood for about 36 hours and the battery was still putting out 12.6v, turned the engine over and it didnt dip below 10v so i think im fairly happy with the battery. 

 

I think i'll try the coolant temp sensor next as you suggest, fairly cheap to do.

 

I don't think its the MAF (or the coils/plugs) due to the lack of issues once up and running, i would have thought any issues there have manifested themselves in day to day driving as well and produced some codes.

 

Cheers

There is a possibility it could be carbon build up in the inlet manifold and on the inlet valves. I personally have no experience of this but a Google search brings up some results. The fact you have no fault codes could perhaps support this theory.

AMD and other specialists can carry out a manual clean which involves removing the inlet manifold and scraping off the carbon deposits. Planehazza a member on here has carried out the clean himself, it may be worth contacting him.

The posts I have read suggest getting an inlet manifold decode every 50000 miles, it should increase power, improve mpg as well as sorting out cold start issues.

I am considering doing this to mine, although at between £400 to £600, I have a bit of saving to do.

I hope this helps and hope you keep us updated on your progress.

Paul.

Hi, Any luck curing your issue? I have a similar issue.

 

1st morning start always a bit rubbish, 2nd or any after perfect.

Mine does this sometimes not every time ( Seat Leon FR ). Haven't looked into it too much. It is on 53k so the suggestion of carbon could be starting to be an issue.