swiss
New Member
- Joined
- March 26, 2003
- Messages
- 9
- Reaction score
- 0
- City, State
- Venice, Ca ::What I'm riding/fixing while my X is out of commission::
- Year, Model & Trim Level
- '85 Kz1000 Police
Hi everyone,
I've been visiting this forum for quite some time now and am compiling some pics/info of troubles and solutions I have had with my vehicle.
I drive a '99 Explorer Sport with a 4.0 SOHC (Vin E) engine. I've had it for three years and to be honest, even though I love my Explorer, it has given me more headaches than I care for
Lately I have been having fuel economy, hesitation in acceleration, rough idle issues. The MIL is on and the trouble codes are:
P0155 O2 Sensor Heater Circuit Malfunction (Bank2, Sensor1)
P0175 Engine Rich (Bank2)
P1152 O2 Sensor fault (Man. Code)
I took it to a smog check station (California) to get the codes. He did a smog test to check the emission results. The hydrocarbon emissions were in the sky (max avg. 34, my test 123)
I replaced the MAF (rich condition usually indicates air intake mixture failure) but the symptoms still persisted and of course the MIL came back on. Just to explain why I changed the MAF, I took it to my friend's house and swapped the MAF from his X to mine and it seemed to run way better, so I changed my MAF.
On a sidenote: the symptoms come and go.
Then I finally decided it was time to order a scantool. I got it today and hooked it up to my car. I monitored the various sensors and found that the O2 sensor Bank2S1 wasn't switching between .2V and .85V at all but rather stayed at .85V while Bank1S1 was continuously switching back and forth. If I remember correctly that indicates a constant rich mixture. Then I saw that the Bank2S2 (the sensor after the CAT on bank 2 was switching slowly as if to compensate for the first sensor not switching.
Now my question:
Does the not switching indicate a bad O2 sensor or is it just running rich constantly? I read in another post about O2 sensors that symptoms of a faulty sensor are:
Excessive fuel consumption, a faulty oxygen sensor can waste 30% of your fuel. --------------------------------------------------------YES
Driveability problems, such as engine surging or hesitation.-----YES
High hydrocarbon emissions, failing an emissions inspection.-----YES
The engine warning light may be on or service flag displayed.----YES
The ecu/computer stores a mixture-related fault code. ---------YES
So, while I know that most O2 related error codes are not the sensor itself I'm wondering if this is the 5% of times when it actually IS a faulty sensor.
Anyone got an opinion/knowledge on that?
P.S. I can post freeze frame (p0175) or graphs if needed.
Thank you all.
Stefan
I've been visiting this forum for quite some time now and am compiling some pics/info of troubles and solutions I have had with my vehicle.
I drive a '99 Explorer Sport with a 4.0 SOHC (Vin E) engine. I've had it for three years and to be honest, even though I love my Explorer, it has given me more headaches than I care for
Lately I have been having fuel economy, hesitation in acceleration, rough idle issues. The MIL is on and the trouble codes are:
P0155 O2 Sensor Heater Circuit Malfunction (Bank2, Sensor1)
P0175 Engine Rich (Bank2)
P1152 O2 Sensor fault (Man. Code)
I took it to a smog check station (California) to get the codes. He did a smog test to check the emission results. The hydrocarbon emissions were in the sky (max avg. 34, my test 123)
I replaced the MAF (rich condition usually indicates air intake mixture failure) but the symptoms still persisted and of course the MIL came back on. Just to explain why I changed the MAF, I took it to my friend's house and swapped the MAF from his X to mine and it seemed to run way better, so I changed my MAF.
On a sidenote: the symptoms come and go.
Then I finally decided it was time to order a scantool. I got it today and hooked it up to my car. I monitored the various sensors and found that the O2 sensor Bank2S1 wasn't switching between .2V and .85V at all but rather stayed at .85V while Bank1S1 was continuously switching back and forth. If I remember correctly that indicates a constant rich mixture. Then I saw that the Bank2S2 (the sensor after the CAT on bank 2 was switching slowly as if to compensate for the first sensor not switching.
Now my question:
Does the not switching indicate a bad O2 sensor or is it just running rich constantly? I read in another post about O2 sensors that symptoms of a faulty sensor are:
Excessive fuel consumption, a faulty oxygen sensor can waste 30% of your fuel. --------------------------------------------------------YES
Driveability problems, such as engine surging or hesitation.-----YES
High hydrocarbon emissions, failing an emissions inspection.-----YES
The engine warning light may be on or service flag displayed.----YES
The ecu/computer stores a mixture-related fault code. ---------YES
So, while I know that most O2 related error codes are not the sensor itself I'm wondering if this is the 5% of times when it actually IS a faulty sensor.
Anyone got an opinion/knowledge on that?
P.S. I can post freeze frame (p0175) or graphs if needed.
Thank you all.
Stefan