5.0L EFI

Use this test procedure ONLY when directed to do so by results of QUICK TEST  or steps in CIRCUIT TESTS . Follow test procedure carefully.

1. When engine stalls in operation or during SELF-TEST, runs rough, or misses, perform the following checks:
   • Perform SYSTEM CHECK, ISC Check. Use TEST II - SYSTEM CHECK , step 1).
   • Check MAP sensor, using TEST G - MAP/BP SENSOR , step 11).
   • Check ISC By-Pass Air, using TEST X - IDLE SPEED CONTROL (BY  -PASS AIR), step 1).
   • Check for, and repair, any bad ground or power connections.
   • Check ignition components (cap, rotor, wires, coil and plugs).
   • Check basic engine components (valves, cam timing, compression, etc.).
2. If detonation (engine knock) occurs, go to TEST H - KNOCK SENSOR , step 1).
3. If no fast idle occurs when A/C is turned on, go to TEST M - NEUTRAL A/C SWITCH , step 1).
4. If shift indicator light is always on or off, go to TEST BB - SHIFT INDICATOR LIGHT (SIL) , step 1).
5. If A/C does not cut-off during wide open throttle (WOT), go to TEST CC - WIDE OPEN THROTTLE , step 1).
6. If engine surges at idle with A/C on, go to TEST CC - WIDE OPEN THROTTLE , step 8).
7. If engine stumbles after hot restart (check HEGO), go to TEST S - 2 .9L, 3.0L & 4.9L EFI FUEL CONTROL, step 15).
8. If engine stalls while parking vehicle, go to TEST P - POWER STEERING PRESSURE SWITCH (PSPS) , step 3).
9. If fuel pump runs with key off, go to TEST T - FUEL PUMP CIRCUIT (INERTIA SWITCH) , step 12).