Rough Starting Problem when cold

[gj124]

2008 Manual GTi, had the car around a year now and often it will struggle to start when cold. The engine will turn over for a few seconds without firing, it hasn't refused to start yet but it seems to be getting worse. I've replaced the battery and it made no difference. The starter seems to be turning the engine on the key and isn't 'clicking' so I'm assuming it's working as it should. I'm thinking it's something to with fuel, maybe a pressure drop when it's been standing for a few hours/days?

I've heard about problems with the high and low pressure pumps. How would I go about diagnosing before throwing parts/money at the problem?

Unfortunately I don't have VCDS so can't do any data logging or scan for codes, no lights on the dash though. Out of interest , what does VCDS cost for post 2008 VAG cars now?

[Clarkj93]

Vcds is 200 or so I believe. You can also get the obd eleven app as an alternative which does about 80% of what vcds does for about 50 quid per year I think. I would start there otherwise you'll be paying for scans or throwing money on the wrong fixes.

Bad throttle body can cause issues starting, mine needs a few revs when cold otherwise eit stalls sometimes and can throw a wobbly if it idles for too long, I just can't be asked to change it just yet as it runs fine when it's moving and easy to fix on the spot. But yeah check for codes first I say.

[GVK]

https://www.gendan.co.uk/product_VCV23.html

Next day delivery from UK

[GreigC]

Your issue is most likely injector related or clogged valves.

[gj124]

I can't really justify the £225 at the moment to be honest so might have a look at OBDeleven. Is getting the injectors out a big job?  Carbon clean is on the (long) list of things to do but the timing belt is the priority so it'll have to wait for now. It's only done 90,000 miles but does a lot of short journeys so I suppose it's very possible that the valves are clogged.

[GreigC]

Out the two it’s most likely an injector. It’s not a huge job but certainly ain’t small… there is few guides online mainly YouTube you can gauge yourself the size of the job. If you take the injectors out you can send them off to have them flow tested/refurbished. Then refit with new seals.

[MattC]

My car had sticky runner flaps and made cold starts a bit rough, wouldn't actually start unless I turned the key to ignition and waited a few seconds before cranking but started every time.

If you don't care about coding, you just need the OBDEleven device. The free plan let's you scan and observe live data.