View Single Post
Old 05-18-2010, 08:29 PM   #7 (permalink)
Master EcoModder
Join Date: Jan 2008
Location: Victoria , Australia.
Posts: 499
Thanks: 20
Thanked 46 Times in 33 Posts
Originally Posted by carbonaltima View Post
How much does an egr valve help in improving fuel economy?
A little hard to say with certainty.
In my car (3.8 GM with 4L60E trans) the EGR operates only on when the cruise control is operating and when that happens the "Lean run" cycle also kicks in.

How much is due to EGR and how much to "lean run" is unknown.

In any case it all happens inside a black box somewhere and my control over it is nil.

Running on cruise means a reduction of about 10% to 15% in fuel numbers on average over my normal driving style.

  Reply With Quote