Check Engine Light Due to Restricted EGR System on Mazda Miata MX-5

The passages for the Exhaust Gas Recirculation (EGR) system can become restricted or clogged causing the Check Engine Light to illuminate. The EGR valve will need to be inspected and the passages cleaned.

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Average mileage: 74,134 (21,206–110,000)
3 model years affected: 1999, 2000, 2010
8 people reported this problem
5 people shared problem details
Engine light comes on when checked I get code 420 which has something to do with the o2 sensor and the catalac converter, both have been changed and the light still comes on.
what would be the cost to have a EGR port cleaning service
2000 Mazda Miata MX-5110,000
EGR valve failed & clogged. EGR replaced but problem quickly resurfaced. Turned out that the passageway in the valve cover was clogged, too, and had to be reamed out. That fixed the problem entirely. Runs great now.
EGR is causing the check engine light to come on. This looks like a recall to me I see that I am not the only one with this problem
The check engine light came on and the code read for the EGR system. I replaced egr valve and the light didn't turn off. I had to clean out the throttle body in order to get the light to turn off.
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