83 c utlass y code egr

[jim83]

Need some ideas- car has 60k on it from new. Fails high speed nox test all others are fine. Do olds y code motors have a history of egr passages coking up and restricting flow?
Thoughts or actual experiances please. Also what is the lesser of the evels for an egr valve- Delco or??
thanks!!!

 

[olds307 and 403]

Yes the passages build up with carbon, stiff wire to clean them out. Go for an AC Delco or whatever you get without too much hassle.

 

[jim83]

So in effect if passenges get coked/ carboned up the lack of flow will cause high nox?
This car has been a struggle to smog. Carb ovehauled off car, replaced tps , o2 sensor etc.
Will try cleaning passagess & if necessary a new egr. Thanks!