Evap System Leak Code P0455 &PO442 I have had this problem for years. I have also managed to be able to beat the state inspection by unplugging the battery and driving it exactly 50 miles pulling into the test station at this time. But alas for over 13 years my system is failing and the jeep is no longer throwing the test at 50 miles. 385 posts · Joined 2012. #1 · May 4, 2014. So I've been chasing an Evap code, P0455, for a year now. 03 4.7. Smoke checked it four times, replaced the leak detection pump, several hoses and two new gas caps. Finally seems to be fixed, wanted to share my solution: The PCV hoses! 2014 Jeep Grand Cherokee check engine light came on. Code P0455 state to either replace the gas cap or purge valve. In a Capless Gas car, you need to clean t Shop for New Auto Parts at 1AAuto.com http://1aau.to/c/240/A/evap-emission-control-system-partsEVAP Explained! It's one of the most common OBDII trouble code What Does Jeep Grand Cherokee Code P0301 Mean? Jeep Grand Cherokee P0301 definition: Cylinder 1 misfire detected. Issue Severity: SEVERE – Stop driving immediately. Repair Urgency: Fix this code immediately (same-day if possible) to avoid ignition failure, catalytic converter damage, and dangerous conditions. Diagnosis: A cylinder 1 misfire can be caused by anything from faulty […] To run this test, the ECM draws a vacuum on the tank. If the ECM detects that the EVAP system is unable to produce or hold a vacuum in a certain amount of time, it records a diagnostic trouble code (DTC) in memory, P0440, “Evaporative Emissions (EVAP) Control System Malfunction,” and illuminates the MIL (malfunction indicator lamp). The P0108 code stands for “Manifold Absolute Pressure/Barometric Pressure High.” It’s logged when the ECM receives a signal from the MAP/BARO sensor circuit that’s above the normal range. Some possible causes of this trouble code include a bad MAP/Baro sensor, MAP/Baro wiring or circuit issues, and a clogged catalytic converter. The P0740 trouble code indicates that the Powertrain Control Module (PCM) detected an abnormal reading from the torque converter clutch circuit. Usually, the PCM goes through numerous checks and the reading needs to be abnormal for a specified amount of time before the light comes on. e7MKLxW.