1998 2.0l 8v Golf GTI will not start from cold

[johnt4321]

Hi, i have just bought another Golf GTI, not had one for years now have bought two in three weeks.

When i try and start the car from cold it just turns over and will not fire, after much trying the engine will eventually fire up and tick over but as soon as you try and touch the throttle it stutters and dies. If you start it again and let it warm up it eventually gets better it will have a slight stutter and then when warm it is ok, from what i have found on the forum it may be the temp sensor or the coil, can anybody through more light on to the subject i don't want to be changing parts for the sake of it with no cure. I have plugged my basic version of VAGCOM on but it is not showing anything up and the distributor is within limits, the previous owner has fitted a new rotor arm and distributor cap, i am leaning towards temperature sender or coil but any help would be appreciated.

[SammoVWT]

I would say the coil would be easier to start if cold as a guess?

Check the value the coolant sensor is reading, does it match the dash?

I'd be leaning towards lack of fuel, the extra air when you touch the throttle is making it stall out due to the mixture being too weak? So maybe fuel filter, but check the values, lambda, air temp sensor & coolant sensor in vag com, make sure its sensible.

If you can see you lambda probe wavelength(or is it amplitude? cant remember!) (around ~0.95 for a working one) and it will at least help to eliminate a few things

Also heard that the ECU relay can be a problem on the GTI's

[johnt4321]

Is there an idiots guide to VAGCOM, i have been messing around with old BMW's for the last few years so have using INPA & DIS software.

[SammoVWT]

I think ross-tech have some guides on their website if i remember correctly. It should tell you all the measuring block codes you need etc.

[johnt4321]

Can somebody please point me in the right direction to finding the temperature sender unit, i have a blue single terminal sensor bolted in to the intake manifold near to the right hand side of the manifold and i have also got a blue single terminal sensor bolted in to the right hand side of the cylinder head, is it either of these or should i be looking for a 2 pin or a 4 pin sender unit, i am looking for the sender unit that can affect poor running from cold and not the one that runs the temperature gauge unless they are one and the same, thanks.

[johnt4321]

Just a quick update, car all sorted, located sensor it was in top hose next to block, swapped sensor 4 pin version car now starts first turn of the key.