UK-POLOS.NET - THE VW Polo Forum

Hi,
I have tried to search for this problem everywhere but cant find a solution.

Short story: 1.6 TDI CAYB 90 HP Tuned. Have to try to start 5-10 times before car starts, can it be EGR/DPF? Anything else I should check?

Long story:
I have a Polo Cross 1.6 TDI(4-cyl. turbo dies. eng. 1.6 l). Previous owner tuned the car to stage 1 i think(dont know if this is relevant for problem).
Problem occurs in cold weather(-5 and lower). When trying to start car the car tries to start but dies pretty fast. It does not respond to the throttle during this period. I have changed the battery so i am excluding this as a problem. I have to try to start the car 5-10 times before it starts up. After starting the car it has no problems driving, and feels normal. Event after turning it off it will start up without any problems. Can this be a problem related to EGR/DPF?

Well it can be all sorts of problems, have you tried ignition on for 7-10s to give the glow plugs time to heat up?

Yes it can be the egr, but also dirty fuel filter

Could be just about anything. Glow spirals, fuel related (HPFP, HP sensor, filter, injector), EGR, DPF, you name it.

Could be fuel filter or connection sucking in air over night leading to extended cranking time ?

Is it only when its -5 or lower? or just worst at those temps

I had the exact same symptoms on my previous VW Lupo. Replacing the coolant temperature sensor solved the issues.
It is quite common that the coolant sensor fails on Lupos (I had to replace it twice during the 11 years I had the car).
I have no idea if the sensors have gotten better since.