Home › Forums › Stay Dirty Lounge › Service and Repair Questions Answered Here › Nissan Sentra 08 (B16) Running Rich › Nissan Sentra 08 (B16) Running Rich December 17, 2019 at 11:24 pm #895524 Richard KirshyParticipant Might check the coolant temp sensor. It does not send a CEL, but a faulty one will fool your ECU into thinking the engine is running hot, so it increases your air/fuel mixture to cool things down. Also check that timing and#1 TDC are correct