Audi S3 Oil Pressure Warning: Common Sensor Failure Fix

I had a nearly identical issue with my 2018 Audi S4 last year. I have some experience working on cars, mainly basic maintenance and diagnostics. The oil pressure warning and error code turned out to be caused by a faulty connection to the oil temp sensor. The automotive sensor itself was fine, but the wiring harness connecting to the temperature sensor had deteriorated. Initially, I was also convinced the engine sensor needed replacement, but the workshop found the real culprit during diagnostics. The repair involved cleaning the connection points and replacing the damaged wiring. Total cost was 95 Euro including labor. The whole job took about an hour at the shop. Before you proceed with any repairs, could you share: Current mileage on your S3, When the warning light first appeared, Whether the light comes on immediately or after driving, If you notice any engine performance issues, The specific error code you are getting This information would help determine if your issue matches what I experienced or if there might be other factors to consider with your temp sensor system.

Last service was done at 114401 KM. The warning light started appearing intermittently about a week ago. Interestingly, it typically comes on after 15-20 minutes of driving when the engine temperature reaches normal operating levels. I have noticed a slight hesitation during acceleration. The error code is P0196. Looking at the car diagnostics report, the oil pressure readings are inconsistent, which aligns with the theory about temp sensor issues. No other warning lights have appeared on the dash. The oil level and quality are fine, I just had a full service completed. Worth noting that while the engine temperature gauge shows normal readings, the oil temperature display occasionally shows erratic values.

Thanks for providing those details. Given that setup matches my S4 experience almost exactly. When my oil temp sensor connection was acting up, I also saw those erratic temp readings and the P0196 code, which specifically relates to engine oil temperature sensor range issues. The inconsistent oil pressure readings through the car diagnostics system, combined with the timing of when the warning appears, strongly suggests a wiring issue rather than a sensor failure. In my case, heat from normal engine operation was causing the damaged wiring to act up, explaining why problems started after reaching operating temperature. The acceleration hesitation you mentioned is likely the car entering a protective mode when receiving inconsistent temp sensor data. This exact behavior happened with my S4 before the repair. Looking at your symptoms versus my experience: Same error code P0196, Similar timing of warning light appearance, Matching erratic oil gauge behavior, Comparable performance impact, Recent service ruling out oil quality issues Based on this, I strongly suspect you are dealing with the same wiring harness deterioration that affected my car. The repair should be relatively straightforward and significantly cheaper than replacing the entire oil sensor assembly. Would recommend getting the wiring connection checked first before considering a full temp sensor replacement. Keep tracking those temperature readings, if they become more erratic, best to address this sooner rather than later.

Thanks for the helpful information about the wiring harness. The error symptoms you described match my situation perfectly, especially regarding the timing of the warning light and the erratic temperature readings. I scheduled an appointment with my mechanic for next week to check the wiring connection to the temp sensor. They quoted about 120 Euro for diagnostics and potential wiring repair, which seems reasonable compared to the cost of replacing the entire engine sensor assembly. In the meantime, I have been monitoring the oil temperature display more closely. The inconsistent readings definitely get worse after the engine warms up, just as you described. The hesitation during acceleration also seems more pronounced when the temperature readings are fluctuating. I will update once the mechanic checks the automotive sensor wiring. Hopefully, it will be a straightforward fix like in your case. Really appreciate you sharing your experience, it saved me from unnecessarily replacing the entire oil temperature sensor unit.