This bulletin applies to 2013-2014 Acura RDX, 2015 RDX 2WD and 2015 RDX AWD vehicles. The “tighten fuel cap” message may be on. DTC P0455 (EVAP system large leak) or P0456 (EVAP small leak) may be stored. During short drive cycles, the PCM may misinterpret inputs from the EVAP system. Check the EVAP system for leaks. If no leaks are found, update the PCM using version 3.01.40 or later.
- Confirm the customer’s drive time before the fault was displayed. If the drive time was less than 20 minutes, go to Step 2.
- Confirm that there is no leak in the EVAP system. Turn the ignition on and clear the DTC with the HDS. Go to Inspection Menu, then select EVAP Test and Function Test. If the EVAP system function test passes, check for poor connections or loose terminals at the FTP sensor, the EVAP canister purge valve, the EVAP canister vent shut valve and the PCM.
- Disconnect the vacuum hose from the engine side of the EVAP canister purge valve in the engine compartment, then connect a vacuum pump/gauge to the purge control solenoid valve.
- With ignition on, select EVAP Test again and monitor the EVAP PCS ON and EVAP CVS ON in the multi solenoids.
- Apply about -0.59 inHg of vacuum until the FTP reads 1.90V (too much vacuum can damage the FTP sensor).
- Disconnect the PCS coupler and then check the FTP sensor reading for one minute. If the voltage increases more than 0.2V, this bulletin does not apply. Continue with normal troubleshooting. If voltage does not increase more than 0.2V, turn ignition to off, reassemble all parts and update the PGM-FI software.