A3 2.0 Tdi Coil Light


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Jun 6, 2010
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Can anybody help please? My coil light sometimes wont go off when i go to start my car and takes 2 or 3 attempts for it to go off, does this mean my coils are ******? This is my first diesel so dont know to much about all this coil stuff!
hi mate, its not a coil light, its the glow plug light. It goes off when the glow plugs (or heater plugs) have gone off, they are needed to start the engine when its cold. Audi glow plugs dont usually stay on more than a brief second except in under 10 deg c coolant temp but your relay may be faulty and they may be staying on (will burn out) or the coolant temp sensor is faulty and reporting crazy low temps to the ecu.

Needs checked by someone with basic to medium electrical skills depending on how far you have to go in testing things.

Restarting the car is not helpful, they go off when not needed and if they are staying on constantly then get a sparky to look at it.

If they go off in under a minute or so whenever they come on then the ecu is keeping them on till the engine is running stable and smooth - tho mine on the 1.9 tdi just flick on and straight off unless its freezing in the dark mornings and then they take 20 secs or so, very low temps will have them on much longer like when its snowed overnight, but now in the uk it hould only be seconds at most.
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