As part of the emissions control system, the 2001 Jeep Cherokee emissions control leak detection pump, more commonly known as the LDP, works within the system to prevent evaporative emissions from the vehicle. Evaporative emissions are different than tailpipe emissions since they occur directly from the gasoline stored in the gas tank and engine and are produced when the vehicle is sitting idle as well as when it is running. The 2001 Jeep Cherokee emissions control leak detection pump works like any other leak detection pump in monitoring any problems within the system that traps the gasoline vapors before they escape and cause damage to the environment.
Basically the 2001 Jeep Cherokee emissions control leak detection pump works as part of the system that self-monitors, does routine diagnostic tests as well as adjusts to correct problems. In addition the LDP also produced data that is relayed to the on-board diagnostic system, OBD-ll that stores this information for review by a technician when the vehicle is brought in for service. The OBD-ll generates a list of codes that allows the mechanic (more correctly the technician) to be able to see how the various emission system parts, including the LDP, are working at any given time.
The 2001 Jeep Cherokee emissions control leak detection pump is the first step in the diagnostic test that the vehicle will periodically run on itself. The reason that the LDP is the first test is because it is needed to pump or pressurize and seal the rest of the system to allow the rest of the diagnostic test. If the LDP was malfunctioning, the rest of the emissions system would read as malfunctioning, invalidating all the test results. The system first tests the LDP for leaks, electrical malfunction or damage. Once the 2001 Jeep Cherokee emissions control leak detection pump passes this test, the next step is for the system to electronically signal to the pump to seal off the vent valve and pressurize the rest of the emissions control system. If the vent does not seal, an error code is generate and the rest of the test is stopped. Provided the vent seals correct, the system is closed and pressurized and the test continues.
There are several different parts in the LDP including the solenoid, upper and lower pump, vent values, check valves and an outlet check valve. The electrical components are also included in the pump and must be working correctly for the pump to function and operate. Thankfully the leak detection system is so sophisticated it can identify tiny malfunctions in the LDP and signal problems before there are serious issues within the system.