Welcome to our guide on how to check the EVAP system without a smoke machine. Discover alternative methods to diagnose and troubleshoot your vehicle’s EVAP system efficiently and effectively. Let’s get started!
How To Check Evap System Without Smoke Machine?
Ensure that your system is subjected to a vacuum and monitor its capability to sustain the vacuum.
Pressurize the system and observe its capacity to sustain the pressure.
An alternative method for checking the system, which does not involve smoke or chemicals, is to employ an ultrasonic leak detector.
What is an effective method of checking for leaks in EVAP system?
Smoke testing serves as a prevalent and effective method to precisely locate leaks in a vehicle’s evaporative emissions control system.
During the smoke testing process, it is essential to ensure that the EVAP system remains sealed. While the purge valve is typically closed, a technician usually needs to utilize a scan tool to command the closure of the EVAP system’s vent valve.
To initiate the EVAP system test, I prefer starting with all components intact. Whenever possible, I introduce smoke through the EVAP system’s test port, identifiable by a green cap and commonly located in the engine compartment of the vehicle.
Next, I carefully examine for any smoke escaping from valves, EVAP lines, the fuel cap, the fuel filler neck, and the gas tank.
The presence of smoke indicates a leak, although it may not necessarily identify all leaks. Once a leak is detected, it is promptly repaired, and the test is repeated to ensure the absence of any additional leaks.
If no smoke is observed during the initial test, I introduce smoke through the fuel filler neck and inspect for leaks in the vicinity of the fuel test port that may have been missed during the initial attachment of the smoke tester.
If smoke remains undetectable, I reconnect the smoke machine to the EVAP test port and proceed to test the valves themselves for potential leaks. For example, I might disconnect the hose on the canister side of the purge valve. Since the purge valve is typically closed, any smoke emanating from it at this stage serves as a strong indication of a leak.
The same principle applies to a vent valve that has been commanded closed. If smoke escapes, it could indicate a leak in the valve, a problem within the command circuit (such as a faulty ground preventing valve activation), or an electrical failure. By examining both the circuit and the component, I can swiftly pinpoint the source of the issue.
Additionally, I disconnect electrical connectors while conducting the smoke test. Recently, we encountered a Dodge Caravan in our workshop that showed no sign of a leak until we disconnected the electrical connector at the leak detection pump, ironically causing smoke to pour out of the connector. With the harness in place, there was no indication of a leak.
Will a smoke test help find EVAP problem?
The prevalence of evaporative emissions system leaks in modern vehicles is exceptionally high. Identifying the precise location of these leaks can pose significant challenges. However, employing a smoke machine and conducting a thorough EVAP system smoke test can greatly simplify the task. In this video, Mike Becker from GoTech explains the step-by-step process he follows when performing smoke testing for leak detection.
Can I fix an EVAP leak myself?
The cost of repairing a leak in your vehicle’s EVAP system can vary depending on the location of the leak and the presence of any additional damage. In some cases, the repair expenses can reach up to approximately $600. While it is possible to diagnose the issue yourself using an OBD2 code reader at home, it is advisable to entrust the actual fixing to experienced professionals.
Alternatively, the EVAP system can be assessed without the need for a smoke machine by utilizing alternative methods such as a vacuum gauge, leak detection dye, or a handheld diagnostic tool. These tools offer viable options for identifying potential leaks and diagnosing issues within the EVAP system.
