P0140 does not seem to be O2
surge82x
12-12-2005, 12:35 AM
This is on a 2000 3.1 SE: I've replaced the rear O2 (twice) and front O2 attempting to get rid of a SES light (P0140). Each time that I've replaced it, I've reset the SES. To any avail it is still coming back on with the same code. Does anybody have any ideas on what could cause this other then the actual O2 sensors, it's starting to drive me nuts?
BTW, I've noticed that there is an extra 2 pin connector just sitting there near the coil back (pass side). Was wondering if anybody could lead me in the right directions of what this goes to. I can provide pictures tomorrow of this.
TIA
Randy
BTW, I've noticed that there is an extra 2 pin connector just sitting there near the coil back (pass side). Was wondering if anybody could lead me in the right directions of what this goes to. I can provide pictures tomorrow of this.
TIA
Randy
BNaylor
12-12-2005, 09:47 AM
Since replacing the rear 02 sensor didn't help you'll need to check the wiring from PCM back to the rear 02 sensor. Also you can check voltages such as the 02 sensor heater voltage since it is a heated 02 sensor. You are getting no activity from the rear sensor.
When you get P0140, it means that the H02s voltage is staying between 0.425 - 0.475 volts for at least 100 seconds which is abnormal. It is supposed to switch to a reading lower than that once engine is warmed up and certain operating parameters are met, otherwise P0140 will set.
On the 2 pin connector post a pic. There is a small 3 wire connector behind the ignition coil packs which should be connected to the front 02 sensor and another small 2 wire connector which connects to the jack located on the right side (passenger) of the ignition coil packs.
When you get P0140, it means that the H02s voltage is staying between 0.425 - 0.475 volts for at least 100 seconds which is abnormal. It is supposed to switch to a reading lower than that once engine is warmed up and certain operating parameters are met, otherwise P0140 will set.
On the 2 pin connector post a pic. There is a small 3 wire connector behind the ignition coil packs which should be connected to the front 02 sensor and another small 2 wire connector which connects to the jack located on the right side (passenger) of the ignition coil packs.
richtazz
12-13-2005, 04:04 PM
IF you bought a Bosch branded aftermarket sensor, there is a good chance it's another bad one. Bosch heated sensors are junk. I used to work at Advance Auto Parts, and we warrantied so many, I advised customers to get a Delco.
surge82x
12-13-2005, 04:28 PM
IF you bought a Bosch branded aftermarket sensor, there is a good chance it's another bad one.
That could very well be the case. After I posted I started searching the forums and found a lot of complaints about the bo<i>t</i>ch<i>ed</i> sensors. Guess I should look in to getting a Delco. Was trying to save a few bucks, guess I shot my self in the foot with that one.
That could very well be the case. After I posted I started searching the forums and found a lot of complaints about the bo<i>t</i>ch<i>ed</i> sensors. Guess I should look in to getting a Delco. Was trying to save a few bucks, guess I shot my self in the foot with that one.
surge82x
12-13-2005, 04:32 PM
Here are the Pics of the connector I promised, sorry for the delay. Works been busy.
http://www.rwaweb.com/2Pin-Con-1.jpg
http://www.rwaweb.com/2Pin-Con-2.jpg
http://www.rwaweb.com/2Pin-Con-1.jpg
http://www.rwaweb.com/2Pin-Con-2.jpg
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