CF Veteran
Quote:
Originally Posted by Rockfrog
@ djb383 ... Can you please provide info based on a Jeep OBDII application the verifies your statement? A generic O2 sensor blurb verifies nothing.
Quote:
Here's a pic that I've post numerous times.....the ScanGauge clearly shows the OBD-II system has entered "closed" loop way before 195F. When this pic was snapped, coolant temp was 94F. The O2 sensor is what "closes" the loop, not the coolant temp sensor.Originally Posted by Rjmils
I've been on this forum for a long time and never heard that and would like some more info
Let me ask this question of u.....if the heated O2 sensor reaches operating temp within seconds of motor start-up thus signaling lean/clean running info, why would the system need to wait say +/-10 minutes for coolant temp to reach 195 to start signaling lean/clean running info? The sooner the motor starts running lean/clean the better, no?
Does anyone have an O2 sensor blurb/info stating something different than the blurb/link I post??????
CF Veteran
Quote:
.....and the Factory offered a 180F stat thru the dealerships. I would think that would be good enough as well.Originally Posted by Firestorm500
Factory put in 195* stat. That's good enough for me.
CF Veteran
Quote:
You could think so, but you would be mistaken.Originally Posted by djb383
.....and the Factory offered a 180F stat thru the dealerships. I would think that would be good enough as well.
You're confusing factory original assembly line procedure versus an optional field service replacement for many engines and car lines.
CF Veteran
Quote:
You're confusing factory original assembly line procedure versus an optional field service replacement for many engines and car lines.
I'm not confusing/mistaking anything......195 and 180 r both acceptable by Jeep factory engineers.Originally Posted by Firestorm500
You could think so, but you would be mistaken.You're confusing factory original assembly line procedure versus an optional field service replacement for many engines and car lines.
CF Veteran
Quote:
Fast idle.....motor was cold, but the "loop" was closed.Originally Posted by Rjmils
7000rpm? Lol

CF Veteran
Quote:
The facts are, Jeep dealerships sold a 180F 4.0L t-stat and your engine enters "closed" loop within seconds of cold start-up. When the heated O2 reaches operating temp of 600F-650F is when the loop "closes, NOT when/because coolant temp reaches 195.
Folks.......please quit posting this false info.
http://www.picoauto.com/applications/lambda-sensor.html.
Originally Posted by djb383
Oh my.....how the myths/false info continue to be perpetuated on the Internet and in forums.The facts are, Jeep dealerships sold a 180F 4.0L t-stat and your engine enters "closed" loop within seconds of cold start-up. When the heated O2 reaches operating temp of 600F-650F is when the loop "closes, NOT when/because coolant temp reaches 195.
Folks.......please quit posting this false info.
http://www.picoauto.com/applications/lambda-sensor.html.
Quote:
DJ is absolutely correct. This is a longtime and popular myth. You can verify this on OBDII Cherokees using a bluetooth OBD adapter and Torque Pro. It has an option to show fuel status, and you'll find that when you start the jeep up, it goes into closed loop rather quickly.Originally Posted by Rockfrog
@ djb383 ... Can you please provide info based on a Jeep OBDII application the verifies your statement? A generic O2 sensor blurb verifies nothing.
If I remember to, I'll try to record a video of this later.
CF Veteran
Quote:
Sure, if they live in south Texas, Florida or California. Or Hawaii.Originally Posted by djb383
I'm not confusing/mistaking anything......195 and 180 r both acceptable by Jeep factory engineers.
If they actually want good heat, they put in the 195.
CF Veteran
We see mid-teens every winter. The 180F Stant SuperStat has been in our XJ for 4 plus years. The heater will make u sweat even in mid-teens ambient.
CF Veteran
Quote:
If I remember to, I'll try to record a video of this later.
Thanks Mr. Pockets......................Originally Posted by PocketsEmpty
DJ is absolutely correct. This is a longtime and popular myth. You can verify this on OBDII Cherokees using a bluetooth OBD adapter and Torque Pro. It has an option to show fuel status, and you'll find that when you start the jeep up, it goes into closed loop rather quickly.If I remember to, I'll try to record a video of this later.
Looking forward to the video.....it will be a great teaching aid and myth buster..........and the O2 sensor, not the coolant temp sensor, is what "closes" the loop on all other vehicles, not just Jeeps, as well.
.........and the t-stat does not have to be a 195F.
CF Veteran
Quote:
I ride around in short pants and a t-shirt in mine at 0 degrees, because I have a MOPAR 195* thermostat.Originally Posted by djb383
We see mid-teens every winter. The 180F Stant SuperStat has been in our XJ for 4 plus years. The heater will make u sweat even in mid-teens ambient.
All the while drinking ice cream slushes from Sonic.
Senior Member
I have a 160 degree thermostat in my Firehawk, and it gets plenty damn hot in the car!
Turn your hot water heater "UP" to 160* and see if you can keep your hand under the faucet for more than a half second!
However, for the OP, you should get rid of the "Failsafe" thermostat........
I had two in a row fail open at regular operating temperature.........
Once was in December when we had a super cold snap..........Drove to work for a few days freezing my *** off, cause the Jeep didn't even reach 100 on the gauge...........It was below zero that week
Turn your hot water heater "UP" to 160* and see if you can keep your hand under the faucet for more than a half second!
However, for the OP, you should get rid of the "Failsafe" thermostat........
I had two in a row fail open at regular operating temperature.........
Once was in December when we had a super cold snap..........Drove to work for a few days freezing my *** off, cause the Jeep didn't even reach 100 on the gauge...........It was below zero that week

