Please help - Autotap newbie - several 02 codes
Thread Starter
Teching In
Joined: Mar 2002
Posts: 36
Likes: 0
From: Bristol, CT
Please help - Autotap newbie - several 02 codes Let me first start off by saying my car is pretty doggy right now. I'm getting P0131, P0137, P0151, and P0157 codes all the time. I clear the codes and shortly after once I hammer the gas...the ses light comes on again. Here is a little data I gathered from Atap - please tell me what you think (hopefully I monitored the right data <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> )
Throttle-----B1S1 (volts)----B2S1 (volts)
84.7-----------0.03-----------0.025
80-------------0.025----------0.015
90.6-----------0.03-----------0.015
90.2-----------0.025----------0.015
84.7-----------0.03-----------0.015
83.9-----------0.03-----------0.015
80.8-----------0.03-----------0.015
82-------------0.03-----------0.015
83.9-----------0.03-----------0.02
KR------timing
4---------28
3.6-------29
3.3------29.5
3--------29.5
2.7-------30
2.5------30.5
2.3------30.5
2--------30.5
1.8-------31
Do I need new O2 Sensors? Car (1998) is pretty much stock with approx 80k miles. Only mod is a lid. I don't know anyone around here that can help me with this so I thought I'd ask you guys for a little help. Thanks guys. Much appreciated.
Colin
98 Z28
If I need to get more data just let me know what to monitor and I'll get the data. Thanks!
Throttle-----B1S1 (volts)----B2S1 (volts)
84.7-----------0.03-----------0.025
80-------------0.025----------0.015
90.6-----------0.03-----------0.015
90.2-----------0.025----------0.015
84.7-----------0.03-----------0.015
83.9-----------0.03-----------0.015
80.8-----------0.03-----------0.015
82-------------0.03-----------0.015
83.9-----------0.03-----------0.02
KR------timing
4---------28
3.6-------29
3.3------29.5
3--------29.5
2.7-------30
2.5------30.5
2.3------30.5
2--------30.5
1.8-------31
Do I need new O2 Sensors? Car (1998) is pretty much stock with approx 80k miles. Only mod is a lid. I don't know anyone around here that can help me with this so I thought I'd ask you guys for a little help. Thanks guys. Much appreciated.
Colin
98 Z28
If I need to get more data just let me know what to monitor and I'll get the data. Thanks!
Re: Please help - Autotap newbie - several 02 codes Given that you are getting failures both banks is it possible that you have contaminated the sensors?
From the service manual:
Leaded fuel, silica contamination from uncured, low grade (unapproved) sealant and high oil consumption are possible causes.
From the service manual:
Leaded fuel, silica contamination from uncured, low grade (unapproved) sealant and high oil consumption are possible causes.
Thread Starter
Teching In
Joined: Mar 2002
Posts: 36
Likes: 0
From: Bristol, CT
Re: Please help - Autotap newbie - several 02 codes Well it all started last year when I got my 1st SES light. I drove around for a day or two when it went out. It didn't come back for a while. Now its more frequent. Now that I have Atap I can cure the SES light but it comes right back like I said. Would this be the cause for my car not having the power it once had? Does the O2 sensors effect performance? Thanks for the help.
Colin
Oh..how do those numbers look?
Colin
Oh..how do those numbers look?
Re: Please help - Autotap newbie - several 02 codes If you only recorded the 5 PIDs you listed then I presume the figures you posted took about 2 seconds to collect.
When working correctly O2 sensor voltages should be changing from around 90mV to around 890mV between 1-3 times per second.
Your voltages are not getting above 30mV which means they are not even operating in the correct range.
You mentioned the codes would go away - that is consistent with O2 sensors that are beginning to fail. The MIL will extinguish after a successful diagnostic test has been performed. The test is performed automatically by the PCM while you are driving your vehicle. Sounds like the O2 sensors are now beyond hope - the PCM will illumniate the MIL if the O2 voltage is below 200mV for more than 33 seconds.
I don't know what is causing the high timing at WOT, maybe for your vehicle that is correct.
I am not an EFI technician (nor a mechanic) but
I usually see about 18-22 degrees at WOT. I'm also guessing that the KR is due to the high timing.
Because ALL your O2 sensors have failed, your car is probably running in open loop mode - and you're probably getting poor fuel economy.
Due to open loop mode, the PCM will not be adjusting its fuel/spark delivery for optimal operation. It will be using the base/factory calibrations which are usually not 100% optimised for the condition of your engine (modifications, wear and tear, fuel quality etc).
Regards
Paul
When working correctly O2 sensor voltages should be changing from around 90mV to around 890mV between 1-3 times per second.
Your voltages are not getting above 30mV which means they are not even operating in the correct range.
You mentioned the codes would go away - that is consistent with O2 sensors that are beginning to fail. The MIL will extinguish after a successful diagnostic test has been performed. The test is performed automatically by the PCM while you are driving your vehicle. Sounds like the O2 sensors are now beyond hope - the PCM will illumniate the MIL if the O2 voltage is below 200mV for more than 33 seconds.
I don't know what is causing the high timing at WOT, maybe for your vehicle that is correct.
I am not an EFI technician (nor a mechanic) but
I usually see about 18-22 degrees at WOT. I'm also guessing that the KR is due to the high timing.
Because ALL your O2 sensors have failed, your car is probably running in open loop mode - and you're probably getting poor fuel economy.
Due to open loop mode, the PCM will not be adjusting its fuel/spark delivery for optimal operation. It will be using the base/factory calibrations which are usually not 100% optimised for the condition of your engine (modifications, wear and tear, fuel quality etc).
Regards
Paul
Thread Starter
Teching In
Joined: Mar 2002
Posts: 36
Likes: 0
From: Bristol, CT
Re: Please help - Autotap newbie - several 02 codes So I guess I'll have to replace my O2 sensors. How much are those bad boys and where would be the best place to purchase them? Thanks for the help! You've been a great help. I owe ya one.
<img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
Colin
<img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
Colin
