MiTo Oil Sensor Issues Lead to Multiple Warning Lights

I had almost the same issue with my 2013 Giulietta, very similar car with comparable electronics. I have some experience working on these models, though I typically leave sensor work to professionals. The temperature sensor and oil gauge warnings can definitely be unsettling. In my case, the engine temperature sensor was giving false readings due to a loose connection. The problem was initially intermittent, but eventually, multiple warning lights started appearing consistently. After checking a few basic things like oil level and connections, I took it to a workshop. They diagnosed a faulty wiring connection to the temp sensor, specifically a damaged plug that wasnt making proper contact. The repair involved replacing the connector and securing the wiring properly. Total cost was 95 Euro, which included diagnostic time and parts. Before suggesting specific fixes for your MiTo, it would help to know: Are the warnings constant or intermittent? Did this start suddenly or develop gradually? Have you noticed any actual changes in engine temperature? What are the specific error codes stored? Car sensor issues can be deceptive, as one faulty connection can trigger multiple warnings. Getting the stored error codes would really help narrow down whether its the oil pressure or engine temperature sensor causing the cascade of warnings.

My MiTo has been parked since the warnings started, at 99208 KM after the last service done 2 months ago. The engine sensor warnings are constant and started suddenly during a normal drive. The oil temperature readings jump erratically from normal to high without any noticeable changes in actual engine performance. No fluid leaks visible under the car. The error codes point to P0196 (Engine Oil Temperature Sensor Range/Performance) and P0520 (Engine Oil Pressure Sensor/Switch Circuit). The oil level and condition are good as they were just changed during service. I appreciate your detailed reply about the wiring issue. Your experience with the temp sensor sounds similar. Will have it checked for loose connections first before replacing any parts.

Thanks for providing those details about your MiTo, it really helps clarify the situation. My Giulietta showed very similar symptoms, particularly with the erratic oil temperature readings. The P0196 code paired with the P0520 strengthens the case for a wiring-related issue, similar to what I experienced. Since your oil was recently changed and levels are good, its unlikely to be an actual oil pressure problem. Car diagnostics often show multiple error codes when theres a wiring or connection issue affecting the sensor network. One thing I noticed with my car that might be relevant, the temperature sensor readings would fluctuate most noticeably during the first 10-15 minutes of driving. The oil gauge would also show inconsistent readings during this time. This behavior is typical of a failing sensor connection rather than actual pressure or temperature issues. Before any parts replacement, have the workshop check: 1. Wiring harness condition near the oil temperature sensor 2. Connector integrity at both the sensor and ECU ends 3. Ground connection quality My repair ended up being simple, but finding the exact connection issue took most of the diagnostic time. The car has run perfectly since fixing the wiring, no more warning lights or erratic readings from the oil gauge. Since your symptoms match almost exactly what I experienced, Id bet on a similar root cause. The repair should be relatively straightforward once they locate the specific connection issue.

The symptoms you described match mine exactly, those erratic oil temperature readings and the same error codes were quite concerning at first. Its reassuring to hear your repair ended up being straightforward and relatively inexpensive. Will definitely have them check all the wiring points you mentioned, especially around the temp sensor area. Makes sense to focus on connections first since the oil was just changed and theres no visible leaks. The constant nature of my warnings does sound similar to your faulty connector case rather than an actual oil pressure problem. Just scheduled the workshop visit for next week. They quoted 1 hour diagnostic time which seems reasonable for checking the connections and running full car diagnostics. Will update once they find the root cause, but feeling more confident now that its likely just a sensor or wiring issue rather than something more serious with the engine temperature system itself. Thanks again for sharing your experience, really helped make sense of these warning lights and gave me a good starting point for the repair.