Q8 Temperature Sensor Malfunction Triggers Oil Warnings

I had a similar issue on my 2016 Audi Q7 with the 3.0 TFSI engine. The automotive sensor readings were inconsistent, showing unusual engine temperature spikes followed by oil pressure warnings. The car diagnostics revealed it was actually a wiring harness issue where the temp sensor connector had corroded. The previous owner had a minor coolant leak that dripped onto the connection, causing deterioration over time. The fix required: Removing the old wiring harness, Installing new temp sensor connectors, Updating the ECU software, Testing the engine temperature readings This was not a major repair in terms of mechanical work, but getting an accurate diagnosis was crucial since faulty readings can lead to engine protection mode. The problem never returned after fixing the connection. Worth checking the wiring and connectors before replacing the entire sensor unit. A proper car diagnostics scan should show if its sending erratic signals or no signal at all, which helps narrow down if its the sensor itself or just the connection.

Thanks for sharing your experience. I had those exact symptoms on my Q8 last month, unusual oil gauge fluctuations and engine temperature warnings that kept coming and going. Turned out the engine sensor wiring was damaged, likely from heat exposure over time. The mechanic replaced the entire sensor assembly and recalibrated the car computer. Car has been running perfectly since then with no warning lights. Just wondering, do you remember roughly what the repair cost was for your fix? Also curious if youve had any other sensor-related issues pop up since getting it sorted? My mechanic mentioned these electrical gremlins sometimes travel in pairs.

After checking my records, the recent repair for the faulty engine oil temperature sensor was much cheaper than initially expected, only 95 Euro to fix the cable connection. The mechanic found the plug connection of the component was defective, which caused those erratic readings we discussed. Since getting the automotive sensor fixed, everything has been running smoothly for several months now. No other temperature sensor issues or warning lights have appeared. The engine temperature readings have remained stable, and the oil pressure warnings completely disappeared after the repair. The car diagnostics confirmed it was just that single connection causing all the trouble. Sometimes these electrical issues seem worse than they actually are. Getting the right diagnosis early definitely saved money compared to replacing parts unnecessarily. If your warning lights return, have the mechanic specifically check the wiring connections first. The temp sensor itself is often fine, its usually the connections that fail.

Thanks for the input. Following your advice, I finally got the issue properly diagnosed and fixed. Took it to a different mechanic who actually bothered to run proper car diagnostics instead of just guessing. Turned out two wires near the engine sensor were rubbing against a bracket, which gradually wore down the insulation. Total repair cost was 180 Euro including labor, they replaced the damaged wiring section and added protective sleeve to prevent future wear. The oil gauge and engine temperature readings are now rock steady. No more unusual warning lights or false alarms. Definitely learned my lesson about getting a thorough diagnostic scan before letting anyone start replacing parts. Really glad I asked here first, saved me from another potentially expensive misdiagnosis. The whole repair took under 2 hours and has been problem-free for the past few weeks.