Test D20 - System Check

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

Fig 1: System Check Flow Chart

1. ISC-BPA Check  - On all engines (except 1.9L MPFI or 2.3L Turbo MPFI), if you are here for any reason other than engine stall or no start, go to next step. On 1.9L MPFI and 2.3L Turbo MPFI engines, go to step 3). If engine stalls or if it does not start, attempt to start engine at part throttle. If engine runs rough, go to next step. If engine runs smoothly at part throttle, go to TEST D5  , step 4). If engine does not run (1.9L MPFI and 2.3L Turbo MPFI engine equipped models), go to step 3). If engine does not run (all other models), go to step 2).
2. 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 RPM while cranking, go to TEST B6, step 15).
   MAP VOLTAGE OUTPUT
   
   

   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

3. 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 the following tests depending on engine application:
   • TEST D1  , step 1) for all 1.9L MPFI or 2.3L Turbo MPFI engine equipped models.
   • TEST D5  , step 11) for all 2.3L OHC MPFI engine equipped models.
   • TEST B11  , step 17) for all 2.5L HSC CFI, or 5.0L SEFI engine equipped models.
4. Checking EGR Valve  - Inspect EGR valve for leaking. If valve is fully closed, and vehicle is equipped with a MAF sensor, go to next step; all others go to TEST C1  , step 1). If EGR valve is leaking or not fully seated, replace or repair valve.
5. Checking MAF Sensor Output  - Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect and repair pins as necessary. Install breakout box and connect ECA. With KOEO, and DVOM on 20-volt scale, measure voltage between Test Pin No. 50, at breakout box, and battery negative terminal. If voltage is between .5 and 1.5 volts, and vehicle stalls, go to TEST B31  , step 6). All others go to TEST C1  . If vehicle displays a Continuous Memory Code 56, go to TEST B3, step 10). If vehicle displays a Continuous Memory Code 66, go to TEST B3, step 6).