My first emissions for my c7 didn’t pass

[aenigma]

It didn’t pass but it didn’t fail. The report came back “not ready to test”. It’s a 2017!!  
I was a bit frustrated thinking their computers must be the failure. They told me my car either had work recently, battery change or it’s been sitting so go fix it and return. I drive it every day, no recent work or battery. 
I got back to my office, did some online research and found my Range that I use in my obd port was the cause. 
If any of you have those, remove them for a couple days prior to emissions test and drive your car around. I haven’t researched why it causes an emissions failure, but a lot of people with c7s are having the same issue. 
Once I have a moment to research why that happens, I’ll update. 

[aenigma]

I found what makes sense to me. Copied from a vette forum: 

 

Guys... no need to speculate, I can tell you with a 100% certainty that it's the Range . The logic that Range uses to shutoff AFM also sets a CEL so Range overcomes this by clearing the CEL just before startup so you never see it . Unfortunately the way they clear the CEL also resets all the other monitors .

[Desertdawg]

I had to look up what a “Range” was.  D,oh!

[Vette R & D]

Thanks for the info, I'm about to go through testing and only put one in this year.  I'll take it out a few days before.

[aenigma]

10 hours ago, Vette R & D said:

Thanks for the info, I'm about to go through testing and only put one in this year.  I'll take it out a few days before.

I still haven’t taken mine back. I’m going tomorrow so we’ll see. 

12 hours ago, Desertdawg said:

I had to look up what a “Range” was.  D,oh!

LOL! 
it’s my savior to not clunking as my gears shift. 

[Grape Ape]

I have no idea what a range is either. Does it have anything to do with rover? Or a bullet? A bullet would make more sense as I'd want to shoot it. Glad it's an easy fix.

[TheCMSH]

I remember this being a thing for C5's also.  I was throwing codes at one point, got it fixed, and I think the thread on the Big Board mentioned needing to go through 20-25 driving cycles to get the system "normal"

[aenigma]

So I took it back for emissions today, same thing. Commish, you’re right on. GM says it needs to be driven a lot more to get back to normal. So I’ll be driving on bad tags for awhile. 

[HOXXOH]

3 hours ago, aenigma said:

So I took it back for emissions today, same thing. Commish, you’re right on. GM says it needs to be driven a lot more to get back to normal. So I’ll be driving on bad tags for awhile. 

 

Resets are usually based on ignition cycles and some have a specific driving distance. Some codes reset in 3, some 10, and  but I don't know what it takes for the Range device. If I had to guess, I'd say it'd probably require driving enough to repeatedly open and close the valve. That could be accomplished quicker by driving at a steady speed and alternating with short bursts of hard acceleration. If it tied into the engine temperature, it might require a cooling cycle in between attempts.   

 

Try giving them a call.

1-866-404-6141 or email support at support@rangetechnology.com

Please report your info results.

[aenigma]

47 minutes ago, HOXXOH said:

 

Resets are usually based on ignition cycles and some have a specific driving distance. Some codes reset in 3, some 10, and  but I don't know what it takes for the Range device. If I had to guess, I'd say it'd probably require driving enough to repeatedly open and close the valve. That could be accomplished quicker by driving at a steady speed and alternating with short bursts of hard acceleration. If it tied into the engine temperature, it might require a cooling cycle in between attempts.   

 

Try giving them a call.

1-866-404-6141 or email support at support@rangetechnology.com

Please report your info results.

Oh duh, I didn’t even think of calling range. They must know this issue. Thank you! 

[aenigma]

Here’s what I got back today. 
thanks again Tom! 
 

 

[aenigma]

It was apparently right on their site. 
 

[aenigma]

It took this long to get my emissions to be ready to test. I had to drive it for weeks without the obd port. As soon as my car started lurching last week, I knew the car was back to normal. I’m thinking that lurch is just something c7s do but I like a smooth ride, so I’m putting back in the Range. I passed emissions yesterday after 3 tries during the month. I can’t wait to have this fun again in 2 years. 😂

[HOXXOH]

After hearing a strange sound emanating slightly forward of the RR wheelwell and thinking It might require a trip to a local dealer, I pulled my Range to see if that made a difference. Knowing the AFM valve is in that vicinity and possibly the cause of the whistling noise and that GM might consider the Range as a mod to void that portion of a warranty.

So as long as I was parking the Range in my office, I decided to keep a log of ignition cycles, time between cycles, and miles between cycles until the dumb little 4 cyl light appears to let me know I'm only using half the engine. I'll give you a full report when it's over, so you can plan ahead for your next emissions test and me for my first test.

 

Back during the 1973 oil embargo, I modified my '71 Olds Cutlass to run on 4 cylinders. I got about a 30% better economy on the highway, but suffered such poor performance in town, that I went back to the full 8 after about a month.

 

I bought a Corvette with a V8 and I want to use all 8 cylinders all the time.

[aenigma]

19 hours ago, HOXXOH said:

After hearing a strange sound emanating slightly forward of the RR wheelwell and thinking It might require a trip to a local dealer, I pulled my Range to see if that made a difference. Knowing the AFM valve is in that vicinity and possibly the cause of the whistling noise and that GM might consider the Range as a mod to void that portion of a warranty.

So as long as I was parking the Range in my office, I decided to keep a log of ignition cycles, time between cycles, and miles between cycles until the dumb little 4 cyl light appears to let me know I'm only using half the engine. I'll give you a full report when it's over, so you can plan ahead for your next emissions test and me for my first test.

 

Back during the 1973 oil embargo, I modified my '71 Olds Cutlass to run on 4 cylinders. I got about a 30% better economy on the highway, but suffered such poor performance in town, that I went back to the full 8 after about a month.

 

I bought a Corvette with a V8 and I want to use all 8 cylinders all the time.

I couldn’t agree with you more. I think we all have 8 to use them dammit! 
keep me posted. It seemed about 3 weeks until my car started bucking, which told me it was shifting between the 2. So off I went.