Having problems with your 2002 Ford Taurus ?
P0420 Catalyst system efficiency below threshold bank1 what does this mean? I have a 2002 Ford taurus that recently has had the egr valve replaced, the pcv hose near the manifold was replaced, the egr pressure sensor was replaced...up until the hose was replaced the engine light has been on/off since 21913and its 31813
Check your convertor ,Take it to a muffler shop and let them check the back pressure ,that should tell the story
Repair Help & Product Troubleshooting for 2002 Ford Taurus
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