|
|
P0171-FUEL SYSTEM 1/1 LEAN (CONTINUED) 7. ENGINE MECHANICAL Turn the ignition off. Check for any of the following conditions/mechanical problems. AIR INDUCTION SYSTEM - must be free from leaks. ENGINE VACUUM - must be at least 13 inches in neutral ENGINE VALVE TIMING - must be within specifications ENGINE COMPRESSION - must be within specifications ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks. ENGINE PCV SYSTEM - must flow freely TORQUE CONVERTER STALL SPEED - must be within specifications POWER BRAKE BOOSTER - no internal vacuum leaks FUEL - must be free of contamination FUEL INJECTOR - plugged or restricted injector; control wire not connected to correct injector Are there any engine mechanical problems? Yes >> Repair as necessary. Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE) No >> Go To 11 8. 1/1 O2 SENSOR Ignition on, engine not running. Disconnect the 1/1 O2 Sensor harness connector. With a scan tool, monitor the 1/1 O2 Sensor voltage. O2 Sensor voltage should read 5.0 volts on the scan tool with the con- Connect a jumper wire between the (K41) Signal circuit and the NOTE: The voltage should drop from 5.0 volts to 2.5 volts with Did the O2 Sensor voltage change from 5.0 volts to 2.5 volts Yes >> Replace the O2 Sensor. Perform the POWERTRAIN VERIFICATION TEST. (Refer No >> Go To 9 NOTE: Remove the jumper wire before continuing. HB ENGINE ELECTRICAL DIAGNOSTICS 9 - 231 |