Mazda MX-6 1998, Workshop Manual

Page: 421 / 1282

MECHANICAL [FS]
ldle-up Speed Inspection
1. Perform “ Engine Tune-up Preparation”.
2. Verify that the idle speed is normal.
3. Verify that the idle-up speed is within the
specification.
Load
condition
Idle-up speed (rpm )*1
MTX
ATX
N, P position
D range
E/L ON*2 625— 925 525— 825 525— 825
A/C ON*3 625— 925 500— 800 500— 800
P/S ON*4 550— 850 500— 800
500— 800
*1 : Excludes temporary idle speed drop just after the
electrical loads (E/L) are turned on.
*2 : Headlight is on, Fan switch (3rd or higher) and Cooling
fan are operating.
*3 : A/C switch and fan switch are on.
*4 : Steering wheel is fully turned.
4. If not as specified with all load conditions, inspect
the idle air control valve.
5. If not as specified with some load conditions,
inspect related input switches, harnesses and
connectors.
Idle Mixture Inspection
1. Perform “Engine Tune-up Preparation” .
2. Verify that the idle speed and ignition timing are
within the specification.
3. Insert an exhaust gas analyzer to the tailpipe.
4. Verify that the CO and HC concentrations are
within the regulation.
5. If not, inspect the following.
• On-board diagnostic system
• Heated oxygen sensor (Front, Rear)
• Intake manifold vacuum
• Fuel line pressure
• Ignition timing control
6. If the systems are normal, replace the three way
catalytic converter.
0 1 -1 OA-18