when you start the van it idles very high continuous. code po137.
what does code po137 mean when the van is idling high
on 2004 Chevrolet Express 3500
Possible vacuum leak causing increased engin rpm @ idle. Code PO137= downstream (behind cat. conv.) O2 sensor or it's circuits problem. Have a mechanic perform scan test to confirm!
1 more answer
agree with #1