What does EVAP mean on a scanner?
What does EVAP mean on a scanner?
The Evaporative Emission Control System (EVAP) is used to prevent gasoline vapors from escaping into the atmosphere from the fuel tank and fuel system. The EVAP system usually requires no maintenance, but faults can turn on the Check Engine light and prevent a vehicle from passing an OBD II plug-in emissions test.
What is EVAP testing?
The EVAP system monitor checks for fuel vapor leaks by performing either a pressure or vacuum test on the fuel system. For 1996 through 1999 vehicles, the federal standard allows leaks up to the equivalent of a hole . The EVAP monitor checks for fuel vapor leaks (including a loose or missing gas cap).
How is a smoke machine used to diagnose EVAP?
A smoke machine is a very effective tool for evap system diagnosis. The machine doesn’t merely supply smoke. It has an airflow gauge that shows how much air is flowing through the probe line into the system. The gauge also can show a leak in the system.
What should the pressure be for an EVAP test?
When testing a system, monitor the pressure gauge while adjusting the airflow to .3 to .4 in. per minute of flow. Be careful not to apply pressure higher than the vehicle’s on-board system test pressure. Note: On vehicles that test the evaporative emissions systems using vacuum, apply 5 to 7 in.-H2O pressure maximum.
What is the fault code for the EVAP system?
Some of the common fault codes associated with the EVAP system are as follows: P0440 code means that a leak has been detected or the vapor pressure sensor in the fuel tank has malfunctioned. One indication might be a faint odor of gasoline originating from the gas tank.
What kind of EVAP system does Toyota have?
Vehicle: 2013 Toyota RAV4. Many EVAP system problems can be difficult to test on some vehicles due to how the system is set up. In this Diagnostic Quick Tip, National Field Trainer Jason Gabrenas shows you how to force an EVAP System test on late-model Toyota vehicles using a scan tool.
How do you test the EVAP system monitor?
TEST PROCEDURE 1. Connect the Scan Tool to the data link connector (DLC). Use the Scan Tool to clear any stored DTC’s and to reset the Onboard Diagnostic Monitors. Bring up the Readiness Code for the EVAP System Monitor. 2. Start the engine (cold); IAT PID from 40-100ºF (this step requires a key “off” period of at least 8 hours). 3.
What should the pressure be on the EVAP system?
Be careful not to apply pressure higher than the vehicle’s on-board system test pressure. Note: On vehicles that test the evaporative emissions systems using vacuum, apply 5 to 7 in.-H2O pressure maximum. If the airflow gauge reading remains steady, then there’s a leak in the system.
How does the Auto test work on a Toyota EVAP?
You can either do it manually or automatic. I like things automatic so we’ll go into the Automatic Test Mode and then it tells you what it’s going to do. It activates the vent solenoid, the vent valve and the vacuum pump to draw and release vacuum through the system.
Can You ground solenoids in an EVAP system?
You can manually ground each solenoid instead of using the scan tool; however, the scan tool activation test shows that the ECM has the ability to control the different solenoids. Our test example is a typical evaporative emissions system. The system includes a purge solenoid, a vent solenoid along with a fuel tank pressure switch or sensor.
