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Test Pin Identification

3.8L SPFI-MA (FWD AXODE) TEST PIN WIRE COLOR I.D.

Application Wire Color
Pin 12 (INJ 6) Light Green/Orange
Pin 15 (INJ 5) Tan/Black
Pin 35 (INJ 4) Brown/Light Blue
Pin 37 (VPWR) Red
Pin 39 (INJ 3) Brown/Yellow
Pin 40 (PWR GND) Black/Light Green
Pin 43 (HEGO-F) Red/Black
Pin 44 (HEGO-R)
Continental Gray/Light Blue
Sable & Taurus Dark Blue/Light Green
Pin 46 (SIG RTN) Gray/Red
Pin 49 (TOT) Orange/Black
Pin 57 (VPWR) Red
Pin 58 (INJ 1) Tan
Pin 59 (INJ 2) White
Pin 60 (PWR GND) Black/Light Green
3.8L SPFI-MA (RWD) TEST PIN WIRE COLOR IDENTIFICATION

Application Wire Color
Pin 12 (INJ 6) Light Green
Pin 15 (INJ 5) Tan/Light Blue
Pin 35 (INJ 4) Brown/Light Blue
Pin 39 (INJ 3) Brown/Yellow
Pin 37 (VPWR) Red
Pin 40 (PWR GND) Black/Light Green
Pin 43 (HEGO-L) Tan/Red
Pin 44 (HEGO-R) Tan/Orange
Pin 46 (SIG RTN) Black/White
Pin 57 (VPWR) Red
Pin 58 (INJ 1) Tan
Pin 59 (INJ 2) White
Pin 60 (PWR GND) Black/Light Green
3.8L SPFI-MA SC TEST PIN WIRE COLOR IDENTIFICATION

Application Wire Color
Pin 12 (INJ 6) Light Green
Pin 15 (INJ 5) Tan/Light Blue
Pin 29 (OCT ADJ) Black/White
Pin 35 (INJ 4) Brown/Light Blue
Pin 37 (VPWR) Red
Pin 39 (INJ 3) Brown/Yellow
Pin 40 (PWR GND) Black/Light Green
Pin 43 (HEGO-L) Tan/Red
Pin 44 (HEGO-R) Tan/Orange
Pin 46 (SIG RTN) Black/White
Pin 57 (VPWR) Red
Pin 58 (INJ 1) Tan
Pin 59 (INJ 2) White
Pin 60 (PWR GND) Black/Light Green
MAP SENSOR VOLTAGE OUTPUT

Elevation (Feet) 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

4) Check ACT Sensor  Ensure ambient temperature is greater than 50°F before performing this test. Check and repair any air leaks in front of ACT sensor. Turn ignition off. Install breakout box and connect ECA to breakout box. Set DVOM to 20-volt scale. See TEST DF for schematic. Connect DVOM to test pins No. 25 and 46. Start engine and let idle. Observe voltage as engine warms up. If voltage does not decrease smoothly and stabilize after engine reaches operating conditions, replace ACT sensor; remove breakout box and rerun QUICK TEST. If voltage decreases smoothly and stabilizes when engine reaches operating conditions, system is operating properly at this time. Reconnect all components and rerun QUICK TEST.

5) Visual Inspection Of MAF Sensor  Code 184 indicates MAF sensor value is higher than expected. Code 185 indicates MAF sensor value is lower than expected. Turn ignition off. Check for air leaks between ISC solenoid and MAF sensor. Inspect MAF sensor for oil contamination caused by excessive blow-by or malfunctioning PCV. If problems are found, repair as necessary; clear codes and rerun QUICK TEST. If all checks are okay, go to step 8).

6) Check MAF Sensor  Turn ignition off. Disconnect ECA 60-pin connector. Inspect connector for damaged pins, corrosion, or loose wires. Install breakout box and connect ECA. Set DVOM on 20-volt scale. Start engine and allow to idle until engine reaches normal operating temperature. Measure voltage between MAF signal and test pin 40/60 of breakout box.

If voltage is within acceptable range, system is operating normally at this time. See INTERMITTENTS in the TESTS W/O CODES article in this section. If voltage is not within acceptable range, replace MAF sensor. See MAF SENSOR DATA  for specification. Reconnect all components and rerun QUICK TEST.

Fig 1: MAF Sensor Graph
G91B06941
MAF SENSOR DATA

Engine Condition (1) Voltage
Idle .8
20 MPH 1.0
40 MPH 1.7
60 MPH 2.1
(1) Engine at normal operating temperature.

7) Visual Vacuum Checks  Code 186 indicates pulse width is longer than expected (rich). Code 187 indicates pulse width is shorter than expected (lean). Inspect air cleaner and air inlet duct; replace or repair an necessary. Check for unmetered air between MAF sensor and ISC bypass solenoid. Check all engine vacuum hoses for damage, leaks, blockage and proper routing. Make necessary repairs and rerun QUICK TEST. If all items are okay, go to next step.

8) Check Fuel Pressure  Turn ignition off. Install fuel pressure gauge. Ensure fuel pressure regulator is connected to manifold vacuum (if applicable). Start engine and run at idle. If fuel pressure is within specifications, go to next step. For fuel pressure specifications, see FUEL PRESSURE SPECIFICATIONS article.If fuel pressure is not within specifications, repair fuel pump or fuel pressure regulator as necessary.

9) Check Systems Ability To Hold Fuel Pressure  Turn ignition on, leaving engine off. If fuel pressure remains at specification for 60 seconds, go to next step (for SPFI), or go to TEST H, step 7) (for PFI). If fuel pressure does not remain at specification, repair fuel delivery system as necessary.

10) Cylinder Balance Test  Run KOER SELF-TEST. After last repeated code, wait 5-10 seconds then "goose" throttle lightly (not wide-open throttle). This will activate cylinder balance test. If code 90 is present after test, go back to step 5). If code 90 is not present after test, go to TEST H, step 4).