Carves
12-28-2011, 05:54 PM
Always seems to be a bit of confusion over the "Loop" business ...
Soooo ... maybe this will be useful for somebody.
When, the "Loop" goes from open to closed ... normally depends on the type of 02 sensor fitted.
Old vehicles with non-heated 02 sensors generally relied on exhaust temps to heat the sensor to its operating temp ...
Newer vehicles ... have 02 sensors with a built in heater so that "closed loop" is achieved ASAP.
Coolant temp seems irrellevant to the loop status as it happens within minutes of start up ... regardless of the coolant temp ...
The following piccies were all taken at an ambient temp of 20*c at 09:00 this morning .... and all the temps in the pics are metric ...
17*c = 62*f
19*c = 66*f
20*c = 68*f
21*c = 70*f
22*c = 71.5*f
100*c = 212*f
http://i1143.photobucket.com/albums/n629/carves-oz/Tools%20and%20Test/OL-CL01b.jpg
http://i1143.photobucket.com/albums/n629/carves-oz/Tools%20and%20Test/OL-CL02b.jpg
http://i1143.photobucket.com/albums/n629/carves-oz/Tools%20and%20Test/OL-CL03b.jpg
http://i1143.photobucket.com/albums/n629/carves-oz/Tools%20and%20Test/OL-CL04b.jpg
http://i1143.photobucket.com/albums/n629/carves-oz/Tools%20and%20Test/OL-CL05b.jpg
http://i1143.photobucket.com/albums/n629/carves-oz/Tools%20and%20Test/OL-CL06b.jpg
Sorry I missed out on getting a 18*c piccy ... The temps change too quick & I was trying to roll a smoke ... guess I cant multi-task ... :D
Nope ... my scangauge aint broke ... :D ... "Closed Loop" at a co-incidental coolant temp of about 20*c seems to be a worldwide phenomenon .. ;)
Whilst this is obviously an OBDII display ..... Both OBDI ... and OBDII FSMs state the exact same thing about 02 sensor operation ... i.e. Heated sensors are used to achieve Closed Loop ASAP.
Since we didnt get Renix XJs down here ... I'll defer to a bunch of stuff on NAXJA by eco-mike in that regard.
Soooo ... maybe this will be useful for somebody.
When, the "Loop" goes from open to closed ... normally depends on the type of 02 sensor fitted.
Old vehicles with non-heated 02 sensors generally relied on exhaust temps to heat the sensor to its operating temp ...
Newer vehicles ... have 02 sensors with a built in heater so that "closed loop" is achieved ASAP.
Coolant temp seems irrellevant to the loop status as it happens within minutes of start up ... regardless of the coolant temp ...
The following piccies were all taken at an ambient temp of 20*c at 09:00 this morning .... and all the temps in the pics are metric ...
17*c = 62*f
19*c = 66*f
20*c = 68*f
21*c = 70*f
22*c = 71.5*f
100*c = 212*f
http://i1143.photobucket.com/albums/n629/carves-oz/Tools%20and%20Test/OL-CL01b.jpg
http://i1143.photobucket.com/albums/n629/carves-oz/Tools%20and%20Test/OL-CL02b.jpg
http://i1143.photobucket.com/albums/n629/carves-oz/Tools%20and%20Test/OL-CL03b.jpg
http://i1143.photobucket.com/albums/n629/carves-oz/Tools%20and%20Test/OL-CL04b.jpg
http://i1143.photobucket.com/albums/n629/carves-oz/Tools%20and%20Test/OL-CL05b.jpg
http://i1143.photobucket.com/albums/n629/carves-oz/Tools%20and%20Test/OL-CL06b.jpg
Sorry I missed out on getting a 18*c piccy ... The temps change too quick & I was trying to roll a smoke ... guess I cant multi-task ... :D
Nope ... my scangauge aint broke ... :D ... "Closed Loop" at a co-incidental coolant temp of about 20*c seems to be a worldwide phenomenon .. ;)
Whilst this is obviously an OBDII display ..... Both OBDI ... and OBDII FSMs state the exact same thing about 02 sensor operation ... i.e. Heated sensors are used to achieve Closed Loop ASAP.
Since we didnt get Renix XJs down here ... I'll defer to a bunch of stuff on NAXJA by eco-mike in that regard.