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CF Veteran
Joined: May 2012
Posts: 3,242
Likes: 2
From: Colorado
Year: 1992 Cherokee Sport
Engine: Bone-Stock 242
Senior Member
Joined: Nov 2012
Posts: 521
Likes: 0
From: Oregon
Year: 1996
Model: Cherokee
Engine: 4.0
Im using the Torque app. It shows my upstream O2 is going from .7ish volts to .1ish and back again. It goes up and down like that alot. Bad sensor? The downstream seems to stay around .8ish iirc.
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
An O2 sensor that is switching is functioning. One that is not, is not functioning.
Senior Member
Joined: Nov 2012
Posts: 521
Likes: 0
From: Oregon
Year: 1996
Model: Cherokee
Engine: 4.0
Senior Member
Joined: Nov 2012
Posts: 521
Likes: 0
From: Oregon
Year: 1996
Model: Cherokee
Engine: 4.0
Edit: ill post a couple screenshots of the sensor activity in a bit whe i get home just to clarify and show what theyre doing.
Last edited by Eagle564; May 17, 2013 at 10:56 AM.
Senior Member
Joined: Nov 2012
Posts: 521
Likes: 0
From: Oregon
Year: 1996
Model: Cherokee
Engine: 4.0
The first pic shows the 2 sensors voltage while at idle and operating Temp while parked.
The second pic is after I revved to about 1500 rpms for a couple of seconds.
The third pic is under normal driving conditions around 30mph
My intake manifold pressure was around 37-40 kPa at idle and my MAF rate wasn't showing up. Idk if thats the app malfunctioning or the sensor.
The second pic is after I revved to about 1500 rpms for a couple of seconds.
The third pic is under normal driving conditions around 30mph
My intake manifold pressure was around 37-40 kPa at idle and my MAF rate wasn't showing up. Idk if thats the app malfunctioning or the sensor.
Last edited by Eagle564; May 17, 2013 at 11:42 AM.
Herp Derp Jerp
Joined: Nov 2011
Posts: 18,251
Likes: 17
From: Parham, ON
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Not sure on what the switching rate should be exactly. Basically the sensors bounce between "Rich" and "Lean". In OBD2 Jeeps, the downstream O2 sensor is used in calculating the fuel trim in closed loop modes.
The MAP is dependent on getting good vacuum from the intake manifold. I think in 1996 they still put it on the firewall. The little hose from it to the manifold is brittle and a common failure, resulting in a ton of fuel being used.
The MAP is dependent on getting good vacuum from the intake manifold. I think in 1996 they still put it on the firewall. The little hose from it to the manifold is brittle and a common failure, resulting in a ton of fuel being used.
Moderator of Jeeps
Joined: Jul 2011
Posts: 21,029
Likes: 3
From: Frederick, MD from Cleveland, OH
Year: 1993 YJ Wrangler
Engine: 4.0 I6
Not sure on what the switching rate should be exactly. Basically the sensors bounce between "Rich" and "Lean". In OBD2 Jeeps, the downstream O2 sensor is used in calculating the fuel trim in closed loop modes.
The MAP is dependent on getting good vacuum from the intake manifold. I think in 1996 they still put it on the firewall. The little hose from it to the manifold is brittle and a common failure, resulting in a ton of fuel being used.
The MAP is dependent on getting good vacuum from the intake manifold. I think in 1996 they still put it on the firewall. The little hose from it to the manifold is brittle and a common failure, resulting in a ton of fuel being used.
Herp Derp Jerp
Joined: Nov 2011
Posts: 18,251
Likes: 17
From: Parham, ON
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Seasoned Member
Joined: Jun 2012
Posts: 380
Likes: 4
From: Vancouver BC
Year: 1998
Engine: 4.0
I got a bunch 0f 3/16 plate sitting around and i want to build a new front winch bumper
Question is can i build the whole thing out of 3/16 or will i need thicker steal for the mounts to the unibody?
Ive always used 3/8 for the frame mount but i here some guys are using 3/16 or 1/4 plate
Whats your opinions ?
Question is can i build the whole thing out of 3/16 or will i need thicker steal for the mounts to the unibody?
Ive always used 3/8 for the frame mount but i here some guys are using 3/16 or 1/4 plate
Whats your opinions ?
Last edited by XJ=mistress; May 17, 2013 at 02:40 PM.
Moderator of Jeeps
Joined: Jul 2011
Posts: 21,029
Likes: 3
From: Frederick, MD from Cleveland, OH
Year: 1993 YJ Wrangler
Engine: 4.0 I6