Quote Originally Posted by Kitch View Post
I'm interested in how this works out.
I've recently installed BP Automotive's fan upgrade wiring kit in my stock 2001 4x4 5.3 Chevy Tahoe.
As part of that upgrade BP Automotive sent me a 2002 12212156 O/S to flash to my PCM so that the fans would work properly.

With the small amount of testing I've done so far the fans seem to work okay but I noticed my EGR and AIR had stopped working.
EGR was disabled in the O/S they sent me so I enabled it and set all the EGR DTC's to mach my original O/S but the in last test run I still had no EGR or AIR active.
After reading your posts I'm now being to wonder if my EGR can't actually work with 12212156 O/S?

I know there is debate on the pros and cons of EGR but looking back over my logs of before and after the E-fan install I've lost gas millage @55-65MPH presumably with the EGR not working.
So at this stage I'd like to be able to get it working again.
With the tune loaded in your pcm you can check the readiness monitors to see if they are marked as Not Ready or Not available. If they are Not Available the monitor is not there.
I assume that if the monitor is not there the system won't work either, but that is just an assumption.
Checking the monitor status can be done with any scan tool with monitor status information I assume. I use the Autel AL319 because it is quick and easy to use for this purpose.
They are cheap and I bought my first one at Walmart, and my second one for work I bought from the internet.
I currently see price at around $29.00 but also around 35.00 depending where they are purchased from. Also, I do not sell them, I just recommend them as a cheap tool that is useful. LOL.

Autel AL319.jpg