Coolant temp sensor change and EPC problem


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Nov 20, 2011
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Having some troubles with temp gauge, so going to change the sensor. After the change, should I bleed the coolant system?
Is it enough if I open the coolant cap, start the engine, and put the heater max?

Also having some other troubles... Sometimes if the engine is warm and I stop the engin for eg. fueling, the car wont start without loooong (~5sec) starting. That has been happened about 5 times, but today the engine stopped on trafic lights, and needed long start. Always the EPC light comes on, but after next "normal" start it disappears.
I read some topics that it could be the crank- or camshaft sensor, am I right?

Car is S3 (BAM).

I dont have VAGCOM...
Going worst... The engine stopped while driving (~40mph) but after 1sec it started "automatically".
Car feels strong and dont make any RPM swinging.

Propably I have to start eating noodles, and order the VCDS-cable from Ross-tech...
My old my mk4 golf (Same engine) used to have problems starting while it was warm. I changed the coolant sensor and it sorted it.

Didnt need to bleed the collant system just make sure its cold, Pop the sensor off and and replace it with a new 1. Make sure to remove the old o-ring 1st. Then just top your coolant up and it should be fine.

As for the cutting out it could be the same thing.

Either way changing the coolant temp sensors worth a try as there only about a 10a
Thanks l33h, much appreciate! I have the coolant sensor, and will change that tomorrow.

Today found some friendly Seat driver who had VAGCOM. We found out that the G28 engine speed sensor has given some faults.

Tomorrow I`ll try to change the crank sensor with one from AGU-engine. The part numbers last letter is different compared to my current. It looks exactly the same but the cable is ~10cm longer.. I`ll give it a try..
The crank sensor fixed my problem, and now car is running well. Also changed the coolant sensor, but now there is some air lock (propably), cause temp wont rise over 80celcius (mostly ~70deg).. Have to check that out tomorrow..

Next problem, brake light switch.. Ordered OEM one and should get that on monday.
The joys of being a Audi owner!! I can't remember the amount of stuff I have bought ! Lol

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