Temperature gauge stops working
 

Hello all, I have a 2006 A6 4.2 Quattro. The temp gauge stops working after about 15-30 min, then awhile later the CEL comes on. When I check it, I get a 2181 code. I reset the code, I replaced the temp sensor in back of engine, it works normal again for awhile, but It still keeps going out. Any ideas? I went to dealer they say it's the thermostat $750 to fix. The car does not over heat, runs normal. Please help.

Ok so wheres what you need to do. Verify actual engine temperature when the gauge is claiming cold. If the upper radiator hose is not something higher than 150-160 degrees than the thermostat is sticking and not letting the engine warm up. If its fine, but gauge still doesnt work, wire harness for temp sensor, either the connector or harness.

Ok thank you I'll check, is the connector/harness easy to replace or is it a dealer repair?