I have a 2006 Audi A3 3.2L V6 with a check engine light and code of P2181, which is defined as cooling system performance error: Check ECT Sensor, thermostat, and water pump. The dealer recommended changing both ECT sensors first. I replaced both of the ECT sensors and the check engine light /code is back on. I believe the problem is an intermittent thermostat.

Anyone have the replacement procedure for the thermostat or other suggestions for this engine code? A location of the thermostat would also be a huge help.

Thanks!

I have a 2006 Audi A3 3.2L V6 with a check engine light and code of P2181, which is defined as cooling system performance error: Check ECT Sensor, thermostat, and water pump. The dealer recommended changing both ECT sensors first. I replaced both of the ECT sensors and the check engine light /code is back on. I believe the problem is an intermittent thermostat.

Anyone have the replacement procedure for the thermostat or other suggestions for this engine code? A location of the thermostat would also be a huge help.

Thanks!

I have the Bentley DVD repair manual. It was 75 bucks from ECS, and has complete step by step for tstat replacement. its in the plastic houseing on the right side of the engine, looking from the front of the car, the thing with all the water hoses attaced to it. Looks like a technically easy job, but there is a lot of stuff in the way, to get at the housing.

I know this is an old thread, so the problem may be fixed by now. what was the final diagnosis?