Range AFM Delete and Emissions

[Sparksalot]

Was that taken right after you removed the AFM device or after three or four short trips after you removed the dongle?

If it was right after you took it out, it looks like you are ready as soon as you pull it. It looks like you only have one readiness flag for the evap and I think in most states, they allow one readiness flag to be set. At least that is what one of the ODBII .org sites said.

Actually that's with the device in place, and a Y cable to connect the Blue Driver.

To make it more fun, its actually a 3 way cable. I also have a Scanguage connected full time.

 

[wsteele]

Actually that's with the device in place, and a Y cable to connect the Blue Driver.

To make it more fun, its actually a 3 way cable. I also have a Scanguage connected full time.

Got it. Very interesting.

When you get time, can you pull the Range and then check readiness? When mine is out, my scanner says I have some trip stuff to complete.

 

[wsteele]

I didn't get a chance today to do a fresh start, complete GM trip to test today. The flags that seem to get set when I pull my Range device out, all stayed set today. I did do a quick down and back to a local market and checked the status after each leg, no joy on any resets. I may get a chance to do the whole GM trip test tomorrow, so will report after.

Also, I will also test whether I can reset my readiness flags while keeping it in "Tow Mode" the whole time. Tow Mode keeps the truck in V8 mode all the time, so I am thinking, if I can reset the flags in tow mode, then I never really have to run it in AFM mode when an emissions test comes up. If it works, it may save me some scratch, at least in the short term.

 

[Sparksalot]

I've noticed that using manual shift will also inhibit the AFM.

 

[Sparksalot]

Got it. Very interesting.

When you get time, can you pull the Range and then check readiness? When mine is out, my scanner says I have some trip stuff to complete.

I’m going do do a few more cold start and drive cycles. I’m curious if the emissions alert will disappear.

 

[wsteele]

I’m going do do a few more cold start and drive cycles. I’m curious if the emissions alert will disappear.

Clearly, there is no rush on any of this stuff.

I mean, it isn't like the world's climate change crisis is going anywhere, at least as long as there are grant dollars at stake.

 

[Sparksalot]

Clearly, there is no rush on any of this stuff.

I mean, it isn't like the world's climate change crisis is going anywhere, at least as long as there are grant dollars at stake.

 

[iamdub]

I've noticed that using manual shift will also inhibit the AFM.

His is an '07- No manual shift other than dropping into "3", "2" or "1". Yeah, these gears would keep AFM off, but then you're driving around with higher RPM. Actually, AFM may still engage if you were cruising steadily enough in third. You're fortunate to have them extra gears and TapShift.

 

[Sparksalot]

His is an '07- No manual shift other than dropping into "3", "2" or "1". Yeah, these gears would keep AFM off, but then you're driving around with higher RPM. Actually, AFM may still engage if you were cruising steadily enough in third. You're fortunate to have them extra gears and TapShift.

Good point, I wasn’t thinking about that being an impediment.

 

[wsteele]

I have been driving around with tow mode, while the Range device is out, to force V8 mode (poor man's AFM disable). I was hoping I could complete the ECU's Trip criteria and get the readiness flags that appear to be set when I remove the Range dongle, to understand how much driving I actually have to do to ready the car for emissions testing, all the while, not running in AFM mode.

Today I had a kind of disheartening occurrence as while in two mode, I glanced down and the AFM system was functioning like normal, switching between V4 and V8 mode! Somehow, it seems the ECU got confused about tow mode and didn't disable AFM mode.

I looks like it won't be a reliable strategy for forcing AFM disable while driving the trip criteria miles before an emissions test.

I haven't had the opportunity to do the exact GM Trip test, but so far, around town and a tiny bit of freeway driving, 25 miles and counting, the flags are still set.