TROUBLESHOOTING GUIDE
F-41flowchartTroubleshooting Guide (Steps 4-11)
1
Check for correct intake manifold vacuum at idle. Intake manifold vacuum: More than 450 mmHg (17.7 inHg)
No
Low vacuum: Check for air leakage of intake air system (page F-93)
Yes
2
Go to next step
3
Check for injector operating sound at idle with sound scope or screwdriver
No
Go to Step 6
Go to Step 6
Check if approx. 12V exists at injector connector (W/R) wire
Yes
4
Go to Step 7
5
Disconnect each high-tension lead at idle and check if engine speed decreases equally each time
No
Go to Step 8
Go to Step 8
Check if spark plugs are OK. Plug gap: 1.0-1.1 mm (0.039-0.043 in)
Yes
6
Disconnect each injector connector at idle and check if engine speed decreases equally each time. If OK, go to Step 9. If not OK, check injector for fuel leakage (page F-113)
7
Check if ECU terminal voltages are OK (2D, 2Q and 2X) (page F-128)
No
Check for cause (Refer to 'Check Point for Each Terminal') (page F-132)
Yes
8
Go to next step
9
Check if vacuum is felt at solenoid valve (purge control) at idle
Yes
Check solenoid valve (page F-119)
No
10
Go to next step
11
Try known good ECU and check if condition improves (page F-127)
See also
B-10COMPRESSIONF-7OUTLINE - WIRING DIAGRAMF-93INTAKE AIR SYSTEMF-112FUEL SYSTEMF-113FUEL SYSTEMF-119EVAPORATIVE EMISSION CONTROL SYSTEMF-127CONTROL SYSTEM - Engine Control Unit InspectionF-128CONTROL SYSTEM - Engine Control Unit Terminal Voltage TableF-132CONTROL SYSTEM - Check Point for Each Terminal (continued)G-20IGNITION SYSTEM — SPARK PLUG