2. Monitor the appropriate PIDs.
3. Drive the vehicle for
10 min
at
65-96 km/h {40-60 mph}
to allow the front catalytic converter to reach
operating temperature.
4. Stop the vehicle and leave it in a safe place.
5. Idle the engine.
6. Record PIDs for
1 min
.
7. Select the appropriate PIDs and read the graph.
8. Count the number of times (inversions) that the upstream HO2S graph line actually crosses the
0.5 V
line.
Fig. 31: Identifying HO2S Graph Line (5 Inversions)
Courtesy of MAZDA MOTORS CORP.
9. Count the number of times (inversions) that the downstream HO2S graph line actually crosses the
0.5 V
line.
10. Using the following equation, calculate the value of ratio.
Equation
RATIO = Upstream HO2S inversion divided by downstream HO2S inversion
NOTE:
Do not count the number of peaks. Refer to Fig. 31 .
2007 Mazda MX-5 Miata Sport
2007 ENGINE PERFORMANCE Emission System - MX-5 Miata
Microsoft
Thursday, July 09, 2009 2:38:04 PM
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