7. Unstable idle speed during warm-up Table 1-57 8. Unstable idle speed after warm-up Table 1-58 76 S/N Operation Test Results Actions 1 Turn the ignition switch to ON. Check if there is trouble information records with a diagnostic instrument. Yes Remove the trouble No Next step 2 Check the air filter for smoothness. Yes Next step No Replace 3 Run the engine at an idle speed. Check if the intake air manifold pressure is between 35kPa and 65kPa during warm up. Yes Next step No Remove leakage for the air intake system 4 Stop the engine, and turn on the ignition switch. Connect an adapter between the ECU and the harness.
Check the pin J1-27 and J1-35 of the ECU (signal output end of the intake air temperature sensor and coolant temperature sensor). Yes Next step No Check and repair 5 Take out he connector of the idle speed actuator after warm-up. Check if the rotation speed of the engine is changed. Yes Next step No Replace idle speed actuator 6 Check the coolant temperature sensor for normal operation. Yes Next step No Replace S/N Operation Test Results Actions 1 Turn the ignition switch to ON. Check if there is trouble information records with a diagnostic instrument. Yes Remove the trouble No Next step 2 Turn the ignition switch to ON. Connect an adapter between the ECU and the harness.
Check the voltage of the pin J1-42 (intake air manifold absolute pressure sensor output), J1-27 (intake air temperature sensor output), J1-43 (coolant temperature sensor output), J1-62, J1-06, J1-38 (oxygen sensor output), J1-54, J1-33, J1-53, J1-34 (output to idle speed actuator) of the the ECU. Is the voltage normal? Yes Next step No Repair or replace harness 3 Check the air filter for smoothness. Yes Next step No Replace