DN - Testing Notes

EGR Valve Position Sensor:

DESCRIPTION
The EGR Valve Position (EVP) sensor monitors the position of the EGR valve pintle. The EVP sensor converts the mechanical movement of the pintle into an electrical voltage signal which is relayed to the Powertrain Control Module (PCM). The EVP sensor is a linear potentiometer in which resistance varies with the EGR valve pintle movement. The EVP sensor provides the PCM with information on EGR flow and EGR system failures.

EGR Vacuum Regulator (EVR) Solenoid:

The EGR Vacuum Regulator (EVR) solenoid receives duty cycle or a variable input from the PCM which allows it to control the vacuum level to the EGR valve. The remaining vacuum not used by the EGR valve is vented through the EVR solenoid filter to atmosphere.

NOTE
You should enter this Pinpoint Test only when you have been directed here from Diagnostic Routines, or from pinpoint test step S8.

REMEMBER
This Pinpoint Test is intended to diagnose only the following:

- EVP sensor

- Harness circuits: VREF, EVP, SIG RTN, EVR, VPWR

- EVR solenoid

- EGR valve assembly

- PCM

- EGR and EVR vacuum lines