EGR Port Vacuum Check

Disconnect the vacuum hose (yellow stripe) from the throttle body EGR vacuum nipple and connect a hand vacuum pump to the nipple.

Fig 1: Checking EGR Port Vacuum
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
Start the engine.
Measure engine vacuum at idle.
1. Standard value: 51 kPa (15 in Hg) or more
Reset the vacuum pump to "0" (Release vacuum).
Using a stop watch, measure how long it takes for the vacuum gauge to reach 51 kPa (15 in Hg).
1. Standard value: 1.0 second or less
If it takes more than 1.0 second for the gauge to reach 51 kPa (15 in Hg), the EGR may be restricted and should be cleaned.

Fig 2: Measuring How Long Takes For Vacuum Gauge
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.