All Questions
Tagged with lambda-sensor or o2-sensor
224 questions
10
votes
3
answers
10k
views
What can cause slow oxygen sensor readings?
I have very slow primary (pre-cat) oxygen sensor readings on my 02' Corolla (2ZZ-GE, 141kW N/A).
While trying to investigate the issue, I repeated diagnostics frequently. Before every diagnostic ...
- 101
2
votes
1
answer
3k
views
Interpreting O2 sensor readings
I have a 2001 Honda Prelude SH (Honda H22A4 Engine).
The exhaust has two oxygen sensors; one before the catalytic converter (sensor 1) and one after (sensor 2). Holding at 2500 RPM and sitting still ...
- 4,910
1
vote
1
answer
1k
views
What options do I have for installing an O2 sensor in a cast iron exhaust manifold?
I need to place an O2 sensor in my exhaust manifold. My exhaust manifold is cast iron and I cannot weld a bung on to it. I've also looked around and the shops around me aren't able to weld onto cast ...
- 1,196
9
votes
3
answers
11k
views
Shouldn't my post-cat O2 sensors (lambda probes) be reporting varying numbers?
On my 2002 BMW E46 330Ci, I've been getting error codes 202 Lambda regulating limit Bank1 and 203 Lambda regulating limit Bank2. Here's the angry sensor readings from the INPA software:
I understand ...
- 1,056
5
votes
1
answer
4k
views
How could the code point to a faulty cat, when the O2 signals are normal?
I'm getting code P0420 on an '03 Vibe. The rule of thumb is that this means the catalytic converter is gone. Yet the pre- and post- cat O2 signals appear to indicate that the cat is doing its job.
...
- 1,555
3
votes
1
answer
16k
views
Very high short term fuel trim
I was checking my short term fuel trim numbers and o2 sensor switching speed as I think my post-cat sensor has degraded.
The car is not throwing a code, and I don't believe that there's a hole in the ...
- 1,945
6
votes
2
answers
2k
views
Replaced catalytic converter, O2 sensor went out, Replaced it and check engine light is still on
About a month ago I replaced my catalytic converter, a few weeks later the O2 sensor went out. I replaced that too and I'm still getting a check engine light code for the same sensor. What else should ...
- 61
8
votes
1
answer
479
views
Changing from two heated O2 sensors to a single O2 sensor
I'm going to be removing a Motorcraft 2150 carburetor in a 2.8L V6 and swapping it for a Ford CFI (and ECU) from a 3.8L V6. I've just recently pulled everything (ECU, throttle body, sensors, harnesses,...
- 1,196
4
votes
2
answers
2k
views
P2195 trouble code 2007 Toyota Sienna
I have a P2195 trouble code with my 2007 Toyota Sienna CE. This is
O2 Sensor Signal Biased/Stuck Lean Bank 1 Sensor 1.
It's a little confusing but if I am reading my Haynes manual correctly, the ...
2
votes
3
answers
858
views
EFI engine car failed Emission test?
i have an EFI engine car (Nissan N16 Super Saloon - 2000yr) i bought it 6monthes ago as an used car.
After i bought it, i had check engine lights on, then i drove it to a mechanical shop few times ...
- 105
2
votes
0
answers
93
views
Translating raw CAN responses into meaningful min/max/value
http://www.scangauge.com/support/x-gauge/xgauges-for-cansf-vehicles/
This website lists data reported by certain sensors.
Lets take an example:
Gauge = Short Term Fuel Trim Bank 1
TXD = 07E00106
...
- 1,521
3
votes
2
answers
623
views
My lambda sensor has a collar around it, I can not see how to unscrew it. (2009 Ford Fusion)
I have a Ford Fusion. I am looking at the sensor on top of the exhaust with a collar, and I cannot see how to undo it. I put the image in to show what I'm dealing with.
I don't see a way to fit a ...
4
votes
1
answer
13k
views
Must the voltage of the post-cat O2 sensor cross 0.5V?
I understand that the voltage on the pre-cat O2 sensor must cross 0.5V (by a 0.3V margin). Is it also the case that the voltage on the post-cat sensor must cross 0.5V? The following image clarifies my ...
- 1,555
2
votes
2
answers
127
views
Is it possible for the ECM to even attempt hitting the stoichiometric point if the pre-cat O2 sensor has failed?
If the pre-cat O2 sensor fails, the ECM is no longer able to determine whether the mixture is rich or lean. A pre-cat O2 sensor cannot fail silently, the CEL (check-engine light) will switch on. I am ...
- 1,555
2
votes
1
answer
223
views
2000 Honda Accord O2 Heater error
After replacing the O2 sensor due to fault codes 1166 and 1167, I still get 1167-Heater circuit error. I check resistance through O2 sensor heat, about 17 Ohms. Plug has 14 volts feeding heater. I ...
- 21
2
votes
4
answers
16k
views
Check engine lights came up after Air filter change?
Yesterday I changed air filters in my car (Nissan supper saloon N16 - model year 2000). After installation the check engine light came on when I started the engine and the engine seemed to be running ...
- 105
6
votes
1
answer
1k
views
Why does an engine revving at 3000 rpm produce O2 variations of 1-2 Hz?
To test whether either or both O2 sensors are damaged, one hooks the (black, following Bosch's convention) wire on each sensor and tracks the signal against the ground using an oscilloscope.
When the ...
- 1,555
7
votes
1
answer
1k
views
Locating the O2 sensors and the cat along the exhaust
I gather that the upstream O2 sensor is the one right in the center of this picture. I also gather that the catalytic converter (the "cat") is the bulbous part of the exhaust right behind this sensor.
...
- 1,555
12
votes
1
answer
745
views
Are widebands known to go lazy over time?
I know narrowbands can go lazy with time, but what about widebands?
This is a sequel to the cold-start misfire mystery.
It turns out that we were looking at the wrong PID's for the front O2 sensor ...
- 39.2k
13
votes
2
answers
17k
views
Rough idle @ stoplights - O2 sensors reading zero voltage
I have an '05 4.7L Dodge Dakota that has had an issue with rough idle for over a year now. It seems to only happen after coming to a stop at a traffic light. It seems to happen more often after having ...
- 181
5
votes
1
answer
6k
views
1998 Honda Civic - O2 sensor or catalyst failure?
I have the P0420 code on my 1998 Honda Civic DX (catalyst system efficiency below threshold bank 1). I want to be able to properly diagnose the problem myself without just throwing new parts at it. A ...
- 222
2
votes
2
answers
154
views
My Toyota fails under full throttle but not when feathered
My car is a Toyota MK4 NA Supra and it has a problem I don't understand. When I push the throttle gently, whether in park or in drive, it gradually builds revs and moves but when I push it hard i.e ...
3
votes
3
answers
13k
views
P1135 code on 2003 Toyota RAV4
I have a Toyota RAV4 2003 and the CEL used to come on and off, but now lately it stay on all the time.
I did check with OBD reader and the car had a P1135.
I did check the voltage on upstream and ...
- 31
6
votes
2
answers
20k
views
How to Identify which O2 sensor is faulty WITHOUT readings from the car's system
I have a 2005 Hyundai Accent, and the check engine light is on. I'm almost 100% sure it's the O2 sensor because it's not as fuel efficient as usual... My work schedule conflicts with mechanics around ...
- 61
7
votes
1
answer
22k
views
Is Torque App reliable to read O2 sensor data?
My 2006 Toyota Prius is throwing code P0420 and I used a cheap OBD-II reader with Torque App on Android to check if my O2 sensors are working or not. I tried the maintenance mode to just run the ...
- 1,739
3
votes
1
answer
12k
views
Oxygen sensor malfunction
2005 Toyota Tundra v8
This truck overheats with no radiator fluid loss. Also had power loss. Motor shake. Codes came back with a voltage high/low and both oxygen sensors upstream needed replacement.
...
- 697
7
votes
3
answers
3k
views
2005 Crown Victoria Police Interceptor showing codes P0053, P0054, P0059 and P0060
I have replaced all 4 oxygen sensors and OBD II code still shows codes P0053, 54, 59, and 60. What could be causing this and how do I fix it?
The O2 sensors have 2 white and 2 black wires. Exactly ...
5
votes
1
answer
1k
views
Does exhaust gas pressure impact the output of narrowband lambdas?
In the course of writing this answer I learnt that the current output of wideband lambda sensors is sensitive to exhaust gas pressure.
This technical document for Bosch LSU 4.2 widebands explains how ...
- 39.2k
12
votes
1
answer
3k
views
How do lambda sensors work?
Virtually every modern passenger vehicle today utilizes lambda sensors from the factory.
How critical are they to a vehicle's operation? How do they work?
- 39.2k
6
votes
3
answers
1k
views
2002 VW GTI 1.8T - O2 sensor fault code only when exceeding 70mph
During my last roadtrip when I was driving at about 80mph on the highway (75 speed limit) a pressed the brakes abruptly after being cutoff by another vehicle, then my MIL came on. When I checked the ...
- 403
4
votes
1
answer
739
views
Why would a lambda sensor fail?
I had an early failure of one of the two lambda sensors in my 2011 Toyota Yaris that was driven for approximately 40 000 - 50 000 km at the time of failure. Fortunately, this was replaced for warranty....
- 15.3k
4
votes
2
answers
3k
views
What controls O2 sensor/lambda cycling?
I just replaced the lambda on my 98 Mazda 626 GF 2L because it was showing a signal that was constantly pegged lean and I suspected it was defective.
After replacing the sensor I took the car for a ...
- 15.7k
5
votes
4
answers
14k
views
judging oxygen sensor quality
I was looking at oxygen sensors for my vehicle on rock auto and found large price discrepancies. I saw sensors ranging from $25 up to $100. in general what do the more expensive sensors have that the ...
- 15.7k
0
votes
1
answer
890
views
2002 Honda CRV Suddenly Throwing Multiple Codes and then a Dead Battery
Last night the CEL came on, and I got the codes read on the way home.
P0122: Throttle Position sensor "A" circuit low voltage
P0139: Secondary HO2S12 (heated oxygen sensor - bank 1 sensor 2) circuit ...
- 198
4
votes
1
answer
781
views
My BMW X5 won't stay running
Hello I have a 2003 BMW X5. I just got the engine replace a couple days ago. I went to pick it up but because the shop was done installing the motor but now I have to deal with the other problems I ...
- 41
0
votes
1
answer
3k
views
Where is the engine temperature sensor located on a Mazda 323?
2003 Mazda 323 Astina, 1.8l, I am trying to figure where the engine temperature sensor is located in the car.
How can I tell if it's faulty? I am only guessing it is because the car overheats, the ...
- 41
10
votes
1
answer
3k
views
A most intriguing cold-start misfire mystery
I'm trying to help a friend out with a CEL on his 2009 Merc GLK 280.
Hooked it up to an OBD2 reader and retrieved a single code:
P0300 - 'Random/Multiple Cylinder Misfire Detected', via the 'OBD ...
- 39.2k
5
votes
1
answer
38k
views
How long will my motor last having clogged catalytic converters?
My catalytic converters have been clogged for awhile, and the o2 sensors need changed because of this.
What is it doing to my engine?
And gas mileage for that matter?
If i take out my ...
- 51
0
votes
3
answers
7k
views
Location of O2 sensor on 1990 Toyota pickup
I'm trying to locate the O2 sensor on my 1990 RWD 22R 2.4 Toyota pickup truck.
I've looked all over underneath the car by the driver's side seat. There is no O2 sensor on top of the exhaust pipe, ...
- 1
2
votes
2
answers
1k
views
Using dry moly lube as an alternative to anti-seize
While shopping for some anti-seize for my O2 sensor install, I came across some transmission lube that had me wondering about whether I could use it as an alternative to anti-seize.
It appears to ...
- 39.2k
3
votes
1
answer
2k
views
Low MPG for my Ford Focus 2005
I have been driving this car for some time now (Ford Focus ZX4 2005). I have been seeing 25 - 27 MPG every time I fill up. I drive a little (10 min) in city and then the rest of my destination on the ...
- 33
4
votes
1
answer
102
views
For the love of all things sacred, what technical reason was there for GM to put a different connector on each side for the rear oxygen sensors?
I just busted my knuckles breaking the oxygen sensors free in hopes of swapping them to see if the problem stayed on the driver side or went with the sensor. Only to find out the connectors are ...
- 245
5
votes
1
answer
4k
views
Oxygen sensor PID for 2004 Toyota Camry 4-cyl
My 2004 Toyota Camry with 170k miles is pulling a P0420 code, which I've read can be due to a bad catalytic converter or O2 sensors. I have an OBD-II tool with the DashCommand app on my iPhone. ...
- 53
3
votes
1
answer
2k
views
O2 Sensor - 1998 Toyota Camry 2.2L 4-cyl
I was getting a few error messages p1135 being one of them, which seems to indicate that the O2 1st bank 1st sensor should be replaced.
My car is 4cyl, so there is only one sensor under the hood (pre ...
- 31
14
votes
1
answer
110k
views
Do I have to rely on wire color to correctly wire up an O2 sensor?
It seems that everyone and their grandmother has a different color-code convention for 4-wire O2 sensors, which complicates matters when one is trying to wire up a replacement "universal" O2 sensor.
...
- 39.2k
12
votes
4
answers
3k
views
Is 60/40 solder fine for splicing wires that have to endure hot engine bay temps?
I need to splice the pigtail connectors from my old O2 sensors onto the new O2 sensors since the new connectors have a different shape.
As the sensor is right behind the engine and will experience ...
- 39.2k
4
votes
1
answer
148
views
Why would one install widebands on vehicles that are setup for narrowbands?
A recent post on one of the forums I frequent has piqued my curiosity.
From my limited reading on the topic, widebands do a better job of quantifying air-fuel ratios than their narrowband ...
- 39.2k
1
vote
1
answer
15k
views
Replaced 02 sensors, engine light still on
I recently bought a second hand VW Golf.
It was 'serviced' and MOTed before the guy sold it to me.
He said three 02 sensors were replaced during the servicing.
The day I drove it away, the engine ...
- 11
4
votes
3
answers
13k
views
P0420 in a Prius
EDIT #2: I rescanned, looking at the correct data, and found the rear O2 sensor was definitely bouncing up and down with the forward sensor's lambda reading. Since I have looked for leaks and couldn'...
- 271
2
votes
1
answer
5k
views
Changed O2 Sensor and my mileage went down
I changed the O2 sensor on my 97 Mazda 323 BA 1.8L BP DOCH Lantis and my mileage actually went down. The car had the original sensor in it, with about 200,000 kilometers on it and I replaced it with ...
- 15.7k