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My 93, 3.2l keeps getting a code for the EGR valve system. The code is 32. Which according to the book is " EGR system failure". How is the ECM determining a failure? There is no sensor on the EGR valve itself. The EGR valve is clean and I seem to have good flow from the tube feeding it. So, I ask again what is indicating to the ECM, that there is a problem with the EGR?

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1993 Rodeo, V6, 3.2L,
4x4, 5 speed
130,000 miles
Chicago, Illinois