Exhaust Gas RECIRCULATION (EGR) Low Pressure (LP) Components - EU5/6 And NAS Only
| ITEM | DESCRIPTION |
|---|---|
| 1 | LP EGR cooler |
| 2 | LP EGR valve |
| 3 | LP EGR pressure sensor |
Low Pressure (LP) EGR components fitted to EU5/6 and NAS vehicles comprises a LP EGR valve and a LP EGR cooler.
The LP EGR valve and LP EGR cooler are located on the front right side of the engine. The EGR valve is attached to the top of the EGR cooler with 6 screws. The EGR cooler is secured to the cylinder block with a bracket and 4 bolts.
The LP EGR valve is a solenoid operated valve which is controlled by the PCM. The PCM uses the LP EGR valve to control the amount of exhaust gas being re-circulated from the catalytic converter and Diesel Particulate Filter (DPF) assembly in order to further reduce exhaust emissions. The LP EGR valve is enabled when the engine is at normal operating temperature and under cruising conditions.
The EGR valve receives a 12V supply from the PCM and is controlled using a PWM signal. The PWM duty signal of the solenoid ground is varied to determine the precise amount of exhaust gas delivered into the turbocharger intake air flow from the air filter housing.
The LP EGR valve is operated through its full range at each engine shut down, to clear any carbon deposits that may have built up whilst the engine was running.
In the event of a failure of the LP EGR valve, the LP EGR function will become inoperative. The PCM can monitor the LP EGR valve solenoid for short circuits and store fault codes in the event of failure. The LP EGR valve can also be activated for testing using an approved diagnostic system.