Resistor Value for CAT when hot

MR.K · 04-06-2008, 07:38 PM

Anyone know the resistor value of the Cat sensor when it's hot? The motor cycles to keep it hot ..

racerbob · 04-09-2008, 07:11 PM

I don't think it works that way. I think cat temp is calculated from run time and the post cat O2 sensor. They work most efficiently at 600 deg F and higher. Post cat sensor on a Prius doesn't stay at any fixed value that can be easilly generated to fool the ECU.

hobbit · 04-09-2008, 07:52 PM

Correct -- there's no actual sensor for cat temp, it's inferred.
There are AF/O2 sensor heaters, that's about it...
.
_H*

MR.K · 04-10-2008, 03:03 AM

Thanks ...just thought you could fool it so the ICE would not run to keep it warm ....

Bill Merchant · 04-10-2008, 03:51 AM

Surely you don't want to spew more emissions into the air, do you?

04-06-2008, 07:38 PM	#1
MR.K Member Join Date: Mar 2008 Location: Idaho Posts: 63 My Car: 2008 Prius Package: #2 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Resistor Value for CAT when hot Anyone know the resistor value of the Cat sensor when it's hot? The motor cycles to keep it hot ..

04-09-2008, 07:11 PM	#2
racerbob Senior Member Join Date: Mar 2008 Location: S Florida Posts: 138 My Car: 2008 Prius Package: #6 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Re: Resistor Value for CAT when hot I don't think it works that way. I think cat temp is calculated from run time and the post cat O2 sensor. They work most efficiently at 600 deg F and higher. Post cat sensor on a Prius doesn't stay at any fixed value that can be easilly generated to fool the ECU.

04-09-2008, 07:52 PM	#3
hobbit Senior Member Join Date: Mar 2005 Location: Bahstahn Posts: 2,883 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Re: Resistor Value for CAT when hot Correct -- there's no actual sensor for cat temp, it's inferred. There are AF/O2 sensor heaters, that's about it... . _H*

04-10-2008, 03:03 AM	#4
MR.K Member Join Date: Mar 2008 Location: Idaho Posts: 63 My Car: 2008 Prius Package: #2 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Re: Resistor Value for CAT when hot Thanks ...just thought you could fool it so the ICE would not run to keep it warm ....

04-10-2008, 03:51 AM	#5
Bill Merchant absit invidia Join Date: May 2005 Location: USA \| Oregon \| Portland area \| 97004 \| Posts: 3,949 My Car: 2007 Prius Package: #5 Nominated 6 Times in 1 Post TOTM Awards: 1 Friends: 49	Re: Resistor Value for CAT when hot Surely you don't want to spew more emissions into the air, do you?