Engine Code
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Engine Code
Hello all I have an 04 civic ex that had a p0134 Code, so i went ahead and replaced the air fuel sensor with the correct denso replacement 234-9017 to my knowledge.
Well shortly after replacing the sensor I cleared the codes and whent for a drive, everything seemed fine car drove and felt great. But all was not good, after a while engine light came back and had p0171
, the car also felt like it lacked some power at about 3000 rpm.
I cleared the code and left the car at home, it sat for a couple hours and cooled down. I test drove it again later and all felt fine. i pulled coolant temp, intake temp, intake pressure and short term fuel trim on my scan tool pids. As the car came up to temp i noticed fuel trim climbing up to 46 and the car started to feel like it felt when the light was on earlier for p0171. When i got out i smelled my tailpipe and it smelled as if it was running rich.
Did I just get a faulty air fuel sensor?
I also recently replaced the fuel filter and strainer because i had a gas leak at the top of the pump assembly and the car ran fine until today when i replaced the sensor.
Edit (Ok after reading more posts on here by searching p0171 i found that someone had misfires because of dirty egr passages. Could this be my problem too? Maybe not enough to misfire but enough to run lean?...after going into closed loop and not using the default rich fuel maps??)
Haha i cant stop thinking about it! Drives me nuts not knowing exactly whats wrong. Also sorry for such a long post, its late and I should be asleep lol
Well shortly after replacing the sensor I cleared the codes and whent for a drive, everything seemed fine car drove and felt great. But all was not good, after a while engine light came back and had p0171
, the car also felt like it lacked some power at about 3000 rpm. I cleared the code and left the car at home, it sat for a couple hours and cooled down. I test drove it again later and all felt fine. i pulled coolant temp, intake temp, intake pressure and short term fuel trim on my scan tool pids. As the car came up to temp i noticed fuel trim climbing up to 46 and the car started to feel like it felt when the light was on earlier for p0171. When i got out i smelled my tailpipe and it smelled as if it was running rich.
Did I just get a faulty air fuel sensor?
I also recently replaced the fuel filter and strainer because i had a gas leak at the top of the pump assembly and the car ran fine until today when i replaced the sensor.Edit (Ok after reading more posts on here by searching p0171 i found that someone had misfires because of dirty egr passages. Could this be my problem too? Maybe not enough to misfire but enough to run lean?...after going into closed loop and not using the default rich fuel maps??)
Haha i cant stop thinking about it! Drives me nuts not knowing exactly whats wrong. Also sorry for such a long post, its late and I should be asleep lol
Last edited by GusBuz; Sep 11, 2016 at 12:29 AM.
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Did I just get a faulty air fuel sensor?
Thread Starter
Registered!!
Joined: May 2016
Posts: 179
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From: SoCal
Rep Power: 123 Thread Starter
Registered!!
Joined: May 2016
Posts: 179
Likes: 1
From: SoCal
Rep Power: 123 Re: Engine Code
Drove it this morning, kept an eye on the scan tool pids and everything was fine even after getting up to operating temp. Fuel trim would be less or more depending on engine load and would not go over 20% at any moment.
I will be keeping an eye on it for a few days hopefully it stays this way.
I will be keeping an eye on it for a few days hopefully it stays this way.
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malcolmgrey
7th Generation Civic 2001 - 2005
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Feb 28, 2016 09:21 PM
