2002 Nissan Sentra 1.8L Stalls & Won't Start: P1217, P0506, P0138, P0158, P0117, P0139, P1146 Fault Codes Explained
Hello! I have a 2002 Nissan Sentra 1.8L that won't start — it turns over but fails to ignite. My OBD2 scanner shows eight fault codes: P1217, P0507, P0138, P0158, P0117, P0139, and P1146. I'm trying to understand what could be causing this issue. The car has been acting up gradually after exposure to flooded conditions. I suspect water damage may have played a role in triggering these codes simultaneously. Here's a breakdown of the codes: - P0117: Engine Coolant Temperature (ECT) sensor malfunction - P0138 & P0158 & P0139: Oxygen (O2) sensor readings outside normal range - P0507: Idle Control System (ICS) failure — indicates poor idle stability - P1146: High voltage detected in the O2 sensor, possibly indicating sensor degradation or wiring issues - P1217: Engine overheated condition — suggests possible cooling system failure or thermal sensor fault The car started showing symptoms after driving through shallow water (about 2 inches deep). After that, it would occasionally stall, feel like it was 'suffocating,' and then restart. On one occasion, while driving uphill, the throttle pedal felt unresponsive and the engine sounded like it was redlining at very low RPM. The temperature gauge rose sharply — I opened the hood, turned on heat, let it cool down, and after a few minutes, it would turn over briefly and idle before dying. I’ve noticed that the check engine light has been on since my father owned the vehicle. We've taken it to shops that reset the ECU, but the code persists. I don’t have full ownership history or technical knowledge of prior repairs. I’m looking for guidance on how to diagnose these codes — especially whether water damage could be affecting sensors or wiring. Any advice on next steps (like checking coolant levels, inspecting oil for coolant contamination, testing fuses) would be greatly appreciated.
All these codes appeared suddenly — is it possible they weren't present before? P0117 (ECT sensor), P0138/P0158/P0139 (O2 sensor readings), P0507 (idle control system), P1146 (high voltage O2 sensor), and P1217 (engine overheated). The sudden appearance raises concern — it's unlikely all these faults occurred at once without prior issues. Did the engine overheat? That would explain P1217 and possibly ECT sensor failure.