Egr Replaced By Dbw

[00Silverado4x4]

I attempted to search but essentially how did the DBW system change engine operation to no longer need an EGR valve. I'm not real knowledgeable about either system as the equipment I work on don't even have emission controls. I understand the principle of what the EGR valve did but if there is someone who could give me a run down on how the DBW works negating the need for the EGR would be awesome. Thanks in advance.

[nickvrebel]

as far as I know the two systems have nothing to do with each other. EGR disappeared right around the same time as DBW showed up, but not at the exact same time. MOST 2002 model trucks didn't have EGR, but DBW didn't become common until 2003 (speaking about GM Trucks).

[00Silverado4x4]

So by chance does anybody have any other ideas?

[redvett]

When GM introduced DBW a tech bulletin stated that DBW allowed the de contenting of EGR due to the PCM and the throttle body to modulate the throttle opening to control emissions.

[00Silverado4x4]

Thanks for the reply. I get it now. I'll just have to find the bulletin. Curious how GM stated this change.