EM–4
EM
CO
Normal
Low
High
2GR-FE ENGINE MECHANICAL – ENGINE
HC
High
Rough idle
Rough idle
High
(fluctuating HC reading)
Rough idle
High
(black smoke from exhaust)
(h) Install the 6 ignition coils.
Torque: 10 N*m (102 kgf*cm, 7 ft.*lbf)
(i)
Install the intake air surge tank. (See page FU-17).
10. INSPECT CO/HC
(a) Start the engine.
(b) Run the engine at 2,500 rpm for approximately 180
seconds.
(c) Insert the CO/HC meter testing probe at least 40 cm
(1.3 ft) into the tailpipe during idling.
(d) Check CO/HC concentration at idle and/or 2,500
rpm.
HINT:
Check regulations and restrictions in your area
when performing 2 mode CO/HC concentration
testing (engine check at both idle speed and at
2,500 rpm).
If the CO/HC concentration does not comply with
regulations, perform troubleshooting in the order
given below.
(1) Check A/F sensor and heated oxygen sensor
operation.
(2) See the table below for possible causes, and
then inspect and repair.
Problems
1. Faulty ignitions:
–
Incorrect timing
–
Fouled, shorted or improperly gapped plugs
2. Incorrect valve clearance
3. Leaks in intake and exhaust valves
4. Leaks in cylinders
1. Vacuum leaks:
–
PCV hoses
–
Intake manifold
–
Throttle body
–
Brake booster line
2. Lean mixture causing misfire
1. Restricted air filter
2. Plugged PCV valve
3. Faulty SFI system:
–
Faulty fuel pressure regulator
–
Defective ECT sensor
–
Defective MAF meter
–
Faulty ECM
–
Faulty injectors
–
Faulty throttle position sensor
Causes