2017 Suburban - failed MASS inspection - Question

danyou

TYF Newbie
Joined
Apr 15, 2021
Posts
2
Reaction score
0
Looking for some help. Took my new to me - 2017 Suburban to get inspected. I did not let it heat up enough and it failed the inspection. Mechanic told me to drive it for a few weeks and then bring it back. I did that made sure the Truck was warm and drove it for about an hour before I brought it in to be re-inspected. I failed again. According to the data on the sheet from the test it says CATALYST - NOT READY, OXYGEN SENSOR - NOT READY. This new mechanic who re-tested it said I need to drive for 1 hour for the computer to reset...is this true? Any suggestions?

thanks in Advance!
 

Blackcar

Full Access Member
Joined
Mar 31, 2018
Posts
124
Reaction score
51
It's under warranty for smog system, take it to dealer and tell them it won't pass emissions tests warranty is 8 years. It in owner's manual.
 

89Suburban

Bull in the china shop
Joined
Jan 10, 2013
Posts
6,510
Reaction score
15,079
Location
SE PA
You not running a range device are you? That would cause that to happen. No service engine or code lights?
 

Rygrego

Member
Joined
Dec 15, 2020
Posts
38
Reaction score
24
Location
Mission Viejo, California
You not running a range device are you? That would cause that to happen. No service engine or code lights?
Not true , I have run one through emissions tests twice with zero problem. A code would not be set for monitors not run. I'm betting there was a check engine light prior to the test and a scan tool was used or the battery was disconnected to clear the codes, but after clearing codes all monitors must be rerun at the vehicles leisure under strict parameters.
 
Last edited:

Rygrego

Member
Joined
Dec 15, 2020
Posts
38
Reaction score
24
Location
Mission Viejo, California
Looking for some help. Took my new to me - 2017 Suburban to get inspected. I did not let it heat up enough and it failed the inspection. Mechanic told me to drive it for a few weeks and then bring it back. I did that made sure the Truck was warm and drove it for about an hour before I brought it in to be re-inspected. I failed again. According to the data on the sheet from the test it says CATALYST - NOT READY, OXYGEN SENSOR - NOT READY. This new mechanic who re-tested it said I need to drive for 1 hour for the computer to reset...is this true? Any suggestions?

thanks in Advance!
He told you to drive it to set the monitors. Someone either cleared the ECM with a scan tool or disconnected the battery to clear present codes. You must now drive the vehicle with the fuel gauge between 1/4 and 3/4 from a cold first start of the day to run the mentioned monitors. I am surprised there wasn't a mention that the EVAP monitor had not run.
 
Last edited:

Doubeleive

Wes
Supporting Member
Joined
Nov 7, 2017
Posts
16,874
Reaction score
21,309
Location
Stockton, Ca.
He told you to drive it to set the monitors. Someone either cleared the ECM with a scan tool or disconnected the battery to clear present codes. You must now drive the vehicle with the fuel gauge between 1/4 and 3/4 from a cold first start of the day to run the mentioned monitors. I am surprised there wasn't a mention that the EVAP monitor had not run.
you are talking about something different, 02 sensor and catalyst are not evap codes
 

Doubeleive

Wes
Supporting Member
Joined
Nov 7, 2017
Posts
16,874
Reaction score
21,309
Location
Stockton, Ca.
Looking for some help. Took my new to me - 2017 Suburban to get inspected. I did not let it heat up enough and it failed the inspection. Mechanic told me to drive it for a few weeks and then bring it back. I did that made sure the Truck was warm and drove it for about an hour before I brought it in to be re-inspected. I failed again. According to the data on the sheet from the test it says CATALYST - NOT READY, OXYGEN SENSOR - NOT READY. This new mechanic who re-tested it said I need to drive for 1 hour for the computer to reset...is this true? Any suggestions?

thanks in Advance!
drive for an hour like he said, should try to keep it at 55 as much as possible for as long as possible, take a 1/2 hour trip one way and then turn around drive back. that should set the 02 and catlyst. stop by harbor freight or pretty much any auto parts store and grab a cheapy code reader that will show if the I/M monitor sensors are ready, you should be able to get one for $25-30, when you plug it in the screen will look very similar to this one, if any of the little indicators are blinking then it's not ready, if they are all on solid then it is ready, in many places you are allowed to have 1 not ready and still pass but ask your inspector to confirm that.
im.JPG
 

Rygrego

Member
Joined
Dec 15, 2020
Posts
38
Reaction score
24
Location
Mission Viejo, California
you are talking about something different, 02 sensor and catalyst are not evap codes
I never said it was, I said it's a more common monitor not run when this comes up. Everything mentioned is in the set list of monitors that must be set prior to passing smog. Catalyst, O2 sensor heater and more. Read again what I wrote.
 
Last edited:

Doubeleive

Wes
Supporting Member
Joined
Nov 7, 2017
Posts
16,874
Reaction score
21,309
Location
Stockton, Ca.
I never said it was, I said it's a more common monitor not run when this comes up. Everything mentioned is in the set list of monitor that must be set prior to passing smog. Catalyst, O2 sensor heater and more. Read again what I wrote.
usually, but I have had the same thing happen everything else will set except the 02 and catalyst, driving it for an hour as mentioned above usually solves it
 

Forum statistics

Threads
118,233
Posts
1,624,542
Members
79,246
Latest member
Restmam2k
Top