Posted this solution here because someone had this issue and couldn't resolve it on theyre fabia, couldnt find the thread so shoved it here for now (mods feel free to move it)

 

Now i recently bought a 99 Passat tdi, and it took a while longer to start when warm than when cold! For some the cranking can last ages or even fail to start. So i did the usual things

 

Replace coolant temp sensor - no dice

replace starter - nada

new battery   - uh uh

Timing - nope

 

Then i stumbled on a thread over in tdi club that highlighted this as an issue with a number of vw's audi's etc around 1999.

Now on skodas this year could be totally different.

 

The chap asked me if it started quickly with the cts unplugged - to which it jumps to life immediately!

Turns out the problem is a bad stock map! for which there is a hot start fix. This fix is costly and as its a 1999, that cost me £300 i was in no way going to spend getting it mapped to start properly.

 

So heres the fix:

 

The engines that have this problem have the 4 pin cts, pin (wire 3) is the one to focus on.

Snip that wire! I soldered in extra wire leading to dashboard and linked up a push switch (has to be 'push to break' normally on one) so that it can be held only to crank then released.

Now this caused errors because cts was effectively disconnected, so I joined the wires using a 10,000 ohm resistor, so that when the button is pushed the circuit is still complete and tells the ecu its cold. When released it returns to normal the electricity flowing down path of least resistance.

 

So ok before anyone jumps on any wagons - I dont advocate cutting stock wires, i do realise it masks a problem, and mapping it is the only 'proper' solution....... But for me and many others with cars worth very little and dont wanna spend money on them it solves the problem without any detriment to the car. Works perfectly for me, hope it helps someone else

Edited 25 October, 201312 yr by Lofty79

Fair play to you I'd do that rather than spending £300. Glad you sorted it

Aye its perfect.

This car is to be a 'spend no money unless absoluteky necessary'

that lot cost me around 5quid so a bit hefty haha but saves the starter.