If the ratio is
1.5 or more
or there is no downstream HO2S inversion, the WU-TWC is functioning
properly.
If the ratio is
less than 1.5
, the WU-TWC is not functioning properly. Replace the WU-TWC.
Upstream HO2S Graph Line Example
Fig. 32: Upstream HO2S Graph Line Example
Courtesy of MAZDA MOTORS CORP.
Downstream HO2S Graph Line Example 1
Equation
RATIO = 30 inversions (upstream HO2S inversions) divided by 5 inversions (downstream HO2S
inversions) = 6.0 (good WU-TWC)
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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