Test D20 - System Check

Perform this test ONLY after code 11 is displayed in KOEO SELF-TEST and you have been directed here from CIRCUIT TEST A1 or by DIAGNOSIS BY SYMPTOM TEST.

Fig 1: System Check Flow Chart

1. MAP Check  - Turn key off and disconnect MAP sensor. Connect MAP tester between harness and MAP sensor. Connect banana plugs of tester into DVOM and set DVOM on 20-volt scale. Turn key on and measure sensor output voltage while cranking engine. If DVOM reading is not to specification, go to TEST B6  , step 14). If DVOM reading decreases from specified range, go to next step. If MAP voltage does not reduce to appropriate voltage while cranking, go to TEST B6  , step 15).
   MAP VOLTAGE OUTPUT SPECIFICATIONS
   
   

   Elevation (Ft.)	Voltage Output (Volts)
   0	1.55-1.63
   1000	1.52-1.60
   2000	1.49-1.57
   3000	1.46-1.54
   4000	1.43-1.51
   5000	1.40-1.48
   6000	1.37-1.45
   7000	1.35-1.43

2. EGR Vacuum Check  - Disconnect vacuum hose at EGR valve. DO NOT  plug vacuum line. Start or attempt to start engine. If symptom is driveability related, check to see if vacuum is present at vacuum line. If vehicle is a "No Start", does engine start? If results are negative, go to TEST B11  , step 17).
3. Checking EGR Valve  - Inspect EGR valve for leaking. If valve is fully closed, go to TEST C1  , step 1). If EGR valve is leaking or not fully seated, replace or repair valve.