We live in Boise.
Downstream O2 sensor diagnostic
- Thread starter wsteele
- Start date
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We live in Boise.
Tonyrodz
Resident Resident
Well I'll be dipped
swathdiver
Full Access Member
Cool. The girls bought the truck in Idaho Falls and drove it back. Dealer was great and the truck is better than expected.
Good to hear. While I am sure there are crooked dealers here, just like everywhere, I have to say, most I have dealt with seem to truly take pride in being honest and fair.
Idaho Falls is about 4 hrs East of Boise. We got our last two dogs near Idaho Falls (Rigby). There are a lot of authentic Idahoans there, less so here in the “Big City”.
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FrankU
Full Access Member
Passes NYS emission inspection with flying colors. This is not the first vehicle I've had like this. It's all in the tune.
I am totally in the dark with regard to tuning software with these systems. The only thing I have ever done with EFI was convert a carbureted air-cooled engine to EFI using a Megasquirt ECU and a very primitive fabricated intake manifold under a couple of downdraft carbs turned throttle bodies, so, yeah, in the pitch black....
. Basically, what is happening with "the tune" then is fooling the monitor software into thinking things like the catalyst monitor is completed, when in fact, it hasn't run at all?
FrankU
Full Access Member
There is no fooling anything , just the rear O2 sensors shut off. The rear O2 sensor's keep an eye on the cats and light up if not in spec. The "tune" is proper and the AF is spot on.
But the cat monitor routine in the ECU monitors what the cats are putting out via the downstream O2 sensor, among other things. The cat monitor routine I think is gone through with each ignition cycle. If you turn off the O2 sensors that provide that data to the monitor, how can the monitor complete its routine?
I think with the basic ODB "emissions test", it is mainly the monitors that they look at, along with any codes, MIL, etc.
PS - I am not questioning that you pass your test, I am just trying to understand the how.
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I enjoyed working around Spud Falls for a while back in the late '80s. We had a microwave site up on Iona Butte that shot TV channels all around there and up to Rexburg. Obviously the transport is all fiber now. Beautiful area. Went up to Yellowstone from there one February for a technical meeting and snowmobiled into the Park and stayed overnight at the Old Faithful ski lodge; it was about -25° F when we hit the trail on our way in. That was a blast.
