Code: P0155
Thread Starter
Team Owner
Joined: May 2004
Posts: 26,345
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From: SoCal
Code: P0155
Did a couple of fast accelerations and a hard turn and the YELLOW CHECK ENGINE lite came on. The code was P0155.
Looked it up and read the posts I could find and it is the code for the Passenger side O2 sensor before the cat.
I cleared the code while still driving and the engine lite went off and the car drove great.
Never had this happen before.
If the sensor went bad or loose connection wouldn't the car run bad and the code/lite not clear from the DIC ??
I did do a decarb proceedure a few weeks ago and the car just hit 60K. I have Kooks LT and other mods in my sig.
Should I worry or blow it off......
DH
Looked it up and read the posts I could find and it is the code for the Passenger side O2 sensor before the cat.
I cleared the code while still driving and the engine lite went off and the car drove great.
Never had this happen before.
If the sensor went bad or loose connection wouldn't the car run bad and the code/lite not clear from the DIC ??
I did do a decarb proceedure a few weeks ago and the car just hit 60K. I have Kooks LT and other mods in my sig.
Should I worry or blow it off......
DH
Pro
Joined: Sep 2003
Posts: 731
Likes: 0
From: Calgary Alberta
If the code keeps coming back, you most likely need a new O2 sensor. Replace both of them while you're at it as you will probaply need to replace the other one fairly soon.
If the code does not come back, then you should be OK, and not have to do anything.
If the code does not come back, then you should be OK, and not have to do anything.
Melting Slicks
Joined: Jun 2004
Posts: 3,439
Likes: 6
From: Newark, DE
St. Jude Donor '06
Congrats Howard, you are correct on both counts. It is indeed the passenger-side forward sensor, and yes, you would have continuing driveability issues if it were a sensor failure or wiring problem (barring intermittents).
Ask Charlie to be sure, but I'm fairly certain that he routinely raises the COT protection threshold when tuning. If so, and if you had some piece of crud come loose (maybe from the decarb?), then it could very well have just been a momentary thing when the crud ignited in the cat.
Another possibility is a dirty MAF. When I looked up the diagnostic procedure, there is a comparison made between the IAT (integrated into the MAF in our '04s) and ECT (Engine Coolant Temperature) sensor readings. A dirty or contaminated IAT or MAS would throw off those readings
GL!
Ask Charlie to be sure, but I'm fairly certain that he routinely raises the COT protection threshold when tuning. If so, and if you had some piece of crud come loose (maybe from the decarb?), then it could very well have just been a momentary thing when the crud ignited in the cat.
Another possibility is a dirty MAF. When I looked up the diagnostic procedure, there is a comparison made between the IAT (integrated into the MAF in our '04s) and ECT (Engine Coolant Temperature) sensor readings. A dirty or contaminated IAT or MAS would throw off those readings
GL!
Advanced
Joined: Oct 2005
Posts: 86
Likes: 0
From: Austin TX
I've just gotten through dealing with O2 sensor probs. and my light would even go on and off occasionally. The rear sensors were bad and the fuse for them was popping also. Make sure you check the fuse.
My car had two bad rear sensors and kept popping the fuse and still ran fine, so don't think that resetting the code will solve it. The car was running very rich though.
My car had two bad rear sensors and kept popping the fuse and still ran fine, so don't think that resetting the code will solve it. The car was running very rich though.
Thread Starter
Team Owner
Joined: May 2004
Posts: 26,345
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From: SoCal
Well unfortunately the code wasn't a one time thing.
A few minutes after starting the car the check engine lit comes on every time. I can clear the lite while driving but the code comes right back. I cannot detect any driving degradation.
They were too busy at A&A today
I am going to call the dealer as it was suggested to me that since it is an emmission component it may be covered...........whats the chances of that being true since they are plugged into my KOOK's
Can I jack the car too look for loose/crimped/melted O2 wire or do I need to wait for a hoist???
DH
A few minutes after starting the car the check engine lit comes on every time. I can clear the lite while driving but the code comes right back. I cannot detect any driving degradation.
They were too busy at A&A today
I am going to call the dealer as it was suggested to me that since it is an emmission component it may be covered...........whats the chances of that being true since they are plugged into my KOOK's
Can I jack the car too look for loose/crimped/melted O2 wire or do I need to wait for a hoist???
DH
Melting Slicks
Joined: Jun 2004
Posts: 3,439
Likes: 6
From: Newark, DE
St. Jude Donor '06
Originally Posted by Dirty Howie
Well unfortunately the code wasn't a one time thing.
A few minutes after starting the car the check engine lit comes on every time. I can clear the lite while driving but the code comes right back. I cannot detect any driving degradation.
They were too busy at A&A today
I am going to call the dealer as it was suggested to me that since it is an emmission component it may be covered...........whats the chances of that being true since they are plugged into my KOOK's
A few minutes after starting the car the check engine lit comes on every time. I can clear the lite while driving but the code comes right back. I cannot detect any driving degradation.
They were too busy at A&A today
I am going to call the dealer as it was suggested to me that since it is an emmission component it may be covered...........whats the chances of that being true since they are plugged into my KOOK's
The heated oxygen sensor (HO2S) must reach operating temperature to provide an accurate voltage signal. A heating element inside the HO2S minimizes the time required for the sensor to reach operating temperature. Voltage is provided to the heater by the ignition 3 voltage circuit through a fuse. With the engine running, ground is provided to the heater by the HO2S heater low control circuit, through a low side driver within the powertrain control module (PCM). The PCM commands the heater ON or OFF to maintain a specific HO2S operating temperature range. The PCM determines the temperature by measuring the current flow through the heater. When the heater is in the ON state, the PCM will pulse the heater OFF for a duration of 50 ms, once per second. When the heater is in the OFF state, the PCM will pulse the heater ON for a duration of 50 ms, once per second. The PCM monitors the heater current with the engine running. The diagnostic is only run once per ignition cycle. If the PCM detects that the heater current is not within the expected range, the following DTCs will set.
DTC P0135 for HO2S bank 1 sensor 1
DTC P0155 for HO2S bank 2 sensor 1
Conditions for Running the DTC - Heater Current Test :DTC P0155 for HO2S bank 2 sensor 1
- DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0200, P0220, P0300, P0410, P0442, P0446, P0452, P0453, P0455, P0491, P0492, P0496, P1125, P1258, P1516, P2101, P2108, P2135, U0107 are not set.
- The ECT Sensor parameter is more than 50°C (122°F)
- The Ignition 1 Signal parameter is between 10-18 volts
- The MAF Sensor parameter is between 3-40 g/s
- The Engine Speed parameter is between 500-3000 RPM
- The Engine Run Time parameter is more than 120 seconds
GL!
Thread Starter
Team Owner
Joined: May 2004
Posts: 26,345
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From: SoCal
Originally Posted by Mr. Lucky
I didn't realize you were still running stock cats. Unfortunately, if it is happening every time you start the car (consistent w/ no driveability issues), it is probably not the cat. It sounds like the sensor's Heater Current test is failing. Here is the pertinent info from the service manual.
The heated oxygen sensor (HO2S) must reach operating temperature to provide an accurate voltage signal. A heating element inside the HO2S minimizes the time required for the sensor to reach operating temperature. Voltage is provided to the heater by the ignition 3 voltage circuit through a fuse. With the engine running, ground is provided to the heater by the HO2S heater low control circuit, through a low side driver within the powertrain control module (PCM). The PCM commands the heater ON or OFF to maintain a specific HO2S operating temperature range. The PCM determines the temperature by measuring the current flow through the heater. When the heater is in the ON state, the PCM will pulse the heater OFF for a duration of 50 ms, once per second. When the heater is in the OFF state, the PCM will pulse the heater ON for a duration of 50 ms, once per second. The PCM monitors the heater current with the engine running. The diagnostic is only run once per ignition cycle. If the PCM detects that the heater current is not within the expected range, the following DTCs will set.
GL!
The heated oxygen sensor (HO2S) must reach operating temperature to provide an accurate voltage signal. A heating element inside the HO2S minimizes the time required for the sensor to reach operating temperature. Voltage is provided to the heater by the ignition 3 voltage circuit through a fuse. With the engine running, ground is provided to the heater by the HO2S heater low control circuit, through a low side driver within the powertrain control module (PCM). The PCM commands the heater ON or OFF to maintain a specific HO2S operating temperature range. The PCM determines the temperature by measuring the current flow through the heater. When the heater is in the ON state, the PCM will pulse the heater OFF for a duration of 50 ms, once per second. When the heater is in the OFF state, the PCM will pulse the heater ON for a duration of 50 ms, once per second. The PCM monitors the heater current with the engine running. The diagnostic is only run once per ignition cycle. If the PCM detects that the heater current is not within the expected range, the following DTCs will set.
DTC P0135 for HO2S bank 1 sensor 1
DTC P0155 for HO2S bank 2 sensor 1
Conditions for Running the DTC - Heater Current Test :DTC P0155 for HO2S bank 2 sensor 1
- DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0200, P0220, P0300, P0410, P0442, P0446, P0452, P0453, P0455, P0491, P0492, P0496, P1125, P1258, P1516, P2101, P2108, P2135, U0107 are not set.
- The ECT Sensor parameter is more than 50°C (122°F)
- The Ignition 1 Signal parameter is between 10-18 volts
- The MAF Sensor parameter is between 3-40 g/s
- The Engine Speed parameter is between 500-3000 RPM
- The Engine Run Time parameter is more than 120 seconds
GL!
Where did you get that I have stock cats??????
I have the Kook's/High flow/X-pipe to the Z06 exhaust.
Haven't cleaned the MAF since the H/C job and it was clean then.
Charlie did adjust the tune a few weeks ago before WSIR
Yesterday I got code P0154 !!!!! with the P0155...cleared both and only the P0155 is returning.
I don't see/feel any power loss. Will WOT be affected. I got another track day in 2 weeks
DH
Team Owner
Joined: Jan 2006
Posts: 20,800
Likes: 59
From: Tellico Village, Tn
St. Jude Donor '08
How long have you had the headers on. I had the same problem. It seems that the sealant used on the 02 sensor would melt down onto the probe, causing my check engine light to come. Replaced it with a higher temp sealant, no more praoblems
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Thread Starter
Team Owner
Joined: May 2004
Posts: 26,345
Likes: 231
From: SoCal
Originally Posted by RamonaC5
How long have you had the headers on. I had the same problem. It seems that the sealant used on the 02 sensor would melt down onto the probe, causing my check engine light to come. Replaced it with a higher temp sealant, no more praoblems
Thanks...will make sure we check for that
DH
Melting Slicks
Joined: Jun 2004
Posts: 3,439
Likes: 6
From: Newark, DE
St. Jude Donor '06
Originally Posted by Dirty Howie
Bob
Where did you get that I have stock cats??????
I have the Kook's/High flow/X-pipe to the Z06 exhaust.
Where did you get that I have stock cats??????
I have the Kook's/High flow/X-pipe to the Z06 exhaust.
<-- (that's what they will be doing when you ask). In any event, it doesn't sound like a problem with the cat.As I'm sure you probably realize by now, that P0154 points to the same O2 sensor as the 0155 code. Unless you can find something obviously broken, melted or disconnected, I think you should probably just bite the bullet and have A&A take a look at it. I'm sure the dealer could diagnose it, but being unfamiliar with your mods, they might very well screw something else up in the process.
You have to ask yourself one question.
"Do I feel lucky?
Well do ya, punk?"
Thread Starter
Team Owner
Joined: May 2004
Posts: 26,345
Likes: 231
From: SoCal
Originally Posted by Mr. Lucky
That's what I thought, but you said earlier, "since it is an emmission component it may be covered." There is ZERO chance that a dealer will cover you for aftermarket high-flow cats <-- (that's what they will be doing when you ask). In any event, it doesn't sound like a problem with the cat.
As I'm sure you probably realize by now, that P0154 points to the same O2 sensor as the 0155 code. Unless you can find something obviously broken, melted or disconnected, I think you should probably just bite the bullet and have A&A take a look at it. I'm sure the dealer could diagnose it, but being unfamiliar with your mods, they might very well screw something else up in the process.
You have to ask yourself one question.
"Do I feel lucky?
Well do ya, punk?"
<-- (that's what they will be doing when you ask). In any event, it doesn't sound like a problem with the cat.As I'm sure you probably realize by now, that P0154 points to the same O2 sensor as the 0155 code. Unless you can find something obviously broken, melted or disconnected, I think you should probably just bite the bullet and have A&A take a look at it. I'm sure the dealer could diagnose it, but being unfamiliar with your mods, they might very well screw something else up in the process.
You have to ask yourself one question.
"Do I feel lucky?
Well do ya, punk?"
But if it is a bad sensor.......they could replace it if they were VERY mod friendly.
But I'm sure I will be seeing Andy or Charlie about it. I'm just suprized I don't see/feel ANY performance/drivability degradation.
Thanks for your help Bob
DH
