Code 44 -Oxygen Sensor (Left Bank Lean)
Thread Starter
Drifting
Joined: May 2007
Posts: 1,426
Likes: 165
From: Motor City
Code 44 -Oxygen Sensor (Left Bank Lean)
Found my harness side pigtail on the drivers side to have oil all over it. Would this cause a false lean reading if it's shorting out?
Instead of cleaning it up, I've ordered a new one so i'll find out once installed, but wondering if anyone else has experience with oil getting in their harness side connector?
Instead of cleaning it up, I've ordered a new one so i'll find out once installed, but wondering if anyone else has experience with oil getting in their harness side connector?
Race Director
Joined: Mar 2015
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Found my harness side pigtail on the drivers side to have oil all over it. Would this cause a false lean reading if it's shorting out?
Instead of cleaning it up, I've ordered a new one so i'll find out once installed, but wondering if anyone else has experience with oil getting in their harness side connector?
Instead of cleaning it up, I've ordered a new one so i'll find out once installed, but wondering if anyone else has experience with oil getting in their harness side connector?
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Left bank lean could be the O2 sensor itself or leaks into the exhaust manifold/pipe or even on the intake side (though that should lean both banks). Something not many owners know is the O2 sensor is a normal wear part. Yes something like every time u replace the brakes or tires u should replace the O2 sensor. Can u clear the code at all? Can u swap the O2 sensors? Do u hear any exh leaks on that side of engine?
Troubleshooting by replacing parts is always the most expensive way to troubleshoot 9T3. Unless u want to replace those items anyways. I really dont know how conductive oil is but i have seen pure water that u can drop a power cord in without shorting or tripping anything in the circuit (dont ask how i know). But usually its the contaminants that collect over time that will lead to shorts. Oil is fairly easy to clean up with just alcohol.
Do u have a real time scanner? Can u look at code history with a scanner? Sometimes a scanner pays for its self timely.
Troubleshooting by replacing parts is always the most expensive way to troubleshoot 9T3. Unless u want to replace those items anyways. I really dont know how conductive oil is but i have seen pure water that u can drop a power cord in without shorting or tripping anything in the circuit (dont ask how i know). But usually its the contaminants that collect over time that will lead to shorts. Oil is fairly easy to clean up with just alcohol.
Do u have a real time scanner? Can u look at code history with a scanner? Sometimes a scanner pays for its self timely.
Thread Starter
Drifting
Joined: May 2007
Posts: 1,426
Likes: 165
From: Motor City
Thanks for the responses guys.
Both sensors are in fact brand new. Recently I put a new set of headers on the car and at that time I wired heated o2's, converting the single wire to 3 wire.
The drivers bank was running lean before the conversion (found on a scanner showing BLM's in the 145 range at idle), but never got a check engine for this condition until first start with the new sensors. No noticeable exhaust or vacuum leaks which would contribute, and also fuel pressure checked out at 41psi key on.
After it threw the code I found Ground G104 on the block above the oil filter also had oil on it. While that was being cleaned I noticed the harness side o2 sensor to have oil as well.
Of course, throwing parts at the car is an expensive way to troubleshoot but at $5 for a new harness side o2 connector it's worth a shot.
The scanner I used was on loan, but I just received a cable in the mail and hopefully will have datamaster running this weekend to confirm. Just wondering if anyone on the forum has run into this issues causing the code mentioned.
Both sensors are in fact brand new. Recently I put a new set of headers on the car and at that time I wired heated o2's, converting the single wire to 3 wire.
The drivers bank was running lean before the conversion (found on a scanner showing BLM's in the 145 range at idle), but never got a check engine for this condition until first start with the new sensors. No noticeable exhaust or vacuum leaks which would contribute, and also fuel pressure checked out at 41psi key on.
After it threw the code I found Ground G104 on the block above the oil filter also had oil on it. While that was being cleaned I noticed the harness side o2 sensor to have oil as well.
Of course, throwing parts at the car is an expensive way to troubleshoot but at $5 for a new harness side o2 connector it's worth a shot.
The scanner I used was on loan, but I just received a cable in the mail and hopefully will have datamaster running this weekend to confirm. Just wondering if anyone on the forum has run into this issues causing the code mentioned.
Last edited by 9T3VETTE; Jun 19, 2015 at 04:14 PM.
Thread Starter
Drifting
Joined: May 2007
Posts: 1,426
Likes: 165
From: Motor City
While waiting for the new connector I pulled the drivers side apart to check for leaks again and look at the plugs. Here's what I found, the #7 plug seems to indicate a problem. All the injectors ohm'd out at 12.5-12.6. Here are some pictures.
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Doesnt let u know whether oil or fuel. Left bank lean would mean #7 should look like #1,3,5 but #1,3,7 could still be lean enough for code 44. All those plugs show is #7 is either rich or has oil contamination. How does the right bank of plugs look? BTW how many miles on those plugs? Plugs #1,3,5 look like almost no mileage.
My guess would be a intake gasket leak on that side of intake manifold. Or maybe one of the vacuum fittings on that side of manifold. I would scan it before pulling the intake though.
My guess would be a intake gasket leak on that side of intake manifold. Or maybe one of the vacuum fittings on that side of manifold. I would scan it before pulling the intake though.
Thread Starter
Drifting
Joined: May 2007
Posts: 1,426
Likes: 165
From: Motor City
Doesnt let u know whether oil or fuel. Left bank lean would mean #7 should look like #1,3,5 but #1,3,7 could still be lean enough for code 44. All those plugs show is #7 is either rich or has oil contamination. How does the right bank of plugs look? BTW how many miles on those plugs? Plugs #1,3,5 look like almost no mileage.
My guess would be a intake gasket leak on that side of intake manifold. Or maybe one of the vacuum fittings on that side of manifold. I would scan it before pulling the intake though.
My guess would be a intake gasket leak on that side of intake manifold. Or maybe one of the vacuum fittings on that side of manifold. I would scan it before pulling the intake though.
I'm still working on getting datamaster up and running...but could you educate me what metric when scanning would indicate a vacuum leak on that side of the manifold? I'm guessing IAC....Thanks.
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Thread Starter
Drifting
Joined: May 2007
Posts: 1,426
Likes: 165
From: Motor City
Race Director
Joined: Mar 2015
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how old are the wires might be time
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
IAC hmmmm, AFAIK that is the positon of the idle air bypass and if u had a intake leak i can only guess that would close down some - just guessing here.
I dont have a Datamaster program. I have an AutoXray hand held scanner that does realtime with my OBD 1.5 (OBD I with OBD II ALDL connector) but not data capture that i can down load. U should watch this scan in closed loop only and the only way i can tell this is the open loop number for short term fuel trim "BLM" will not be 128 (or maybe its 138). Yea when the ECM goes open loop it indicates BLM = 128 and controls fuel using the stored "map" data (no longer uses O2 data).
Anyways watching your short term and long term fuel trims should verify your lean condition. Some programs also have a "history" of codes and maybe some data before the CES sets which maybe helpful. U should be able to get a excel table for a current data run - again u can watch the BLM number to see when its closed loop and the BLM is changing. Dont bother to even look at the O2 numbers in closed loop. The lambda narrow band O2 sensor is constantly switching between 100mV and 900mV and unreadable (though the ECM is trending this data for BLM/short term fueling but to fast for u to make sense of it).
Anyways once u have Datamaster in use then try a realtime scan and post a table for us - i have no idea what Datamaster is goona look at or how to interpret it without seeing what it looks at.
Hope this helps.
I dont have a Datamaster program. I have an AutoXray hand held scanner that does realtime with my OBD 1.5 (OBD I with OBD II ALDL connector) but not data capture that i can down load. U should watch this scan in closed loop only and the only way i can tell this is the open loop number for short term fuel trim "BLM" will not be 128 (or maybe its 138). Yea when the ECM goes open loop it indicates BLM = 128 and controls fuel using the stored "map" data (no longer uses O2 data).
Anyways watching your short term and long term fuel trims should verify your lean condition. Some programs also have a "history" of codes and maybe some data before the CES sets which maybe helpful. U should be able to get a excel table for a current data run - again u can watch the BLM number to see when its closed loop and the BLM is changing. Dont bother to even look at the O2 numbers in closed loop. The lambda narrow band O2 sensor is constantly switching between 100mV and 900mV and unreadable (though the ECM is trending this data for BLM/short term fueling but to fast for u to make sense of it).
Anyways once u have Datamaster in use then try a realtime scan and post a table for us - i have no idea what Datamaster is goona look at or how to interpret it without seeing what it looks at.
Hope this helps.
Thread Starter
Drifting
Joined: May 2007
Posts: 1,426
Likes: 165
From: Motor City
IAC hmmmm, AFAIK that is the positon of the idle air bypass and if u had a intake leak i can only guess that would close down some - just guessing here.
I dont have a Datamaster program. I have an AutoXray hand held scanner that does realtime with my OBD 1.5 (OBD I with OBD II ALDL connector) but not data capture that i can down load. U should watch this scan in closed loop only and the only way i can tell this is the open loop number for short term fuel trim "BLM" will not be 128 (or maybe its 138). Yea when the ECM goes open loop it indicates BLM = 128 and controls fuel using the stored "map" data (no longer uses O2 data).
Anyways watching your short term and long term fuel trims should verify your lean condition. Some programs also have a "history" of codes and maybe some data before the CES sets which maybe helpful. U should be able to get a excel table for a current data run - again u can watch the BLM number to see when its closed loop and the BLM is changing. Dont bother to even look at the O2 numbers in closed loop. The lambda narrow band O2 sensor is constantly switching between 100mV and 900mV and unreadable (though the ECM is trending this data for BLM/short term fueling but to fast for u to make sense of it).
Anyways once u have Datamaster in use then try a realtime scan and post a table for us - i have no idea what Datamaster is goona look at or how to interpret it without seeing what it looks at.
Hope this helps.
I dont have a Datamaster program. I have an AutoXray hand held scanner that does realtime with my OBD 1.5 (OBD I with OBD II ALDL connector) but not data capture that i can down load. U should watch this scan in closed loop only and the only way i can tell this is the open loop number for short term fuel trim "BLM" will not be 128 (or maybe its 138). Yea when the ECM goes open loop it indicates BLM = 128 and controls fuel using the stored "map" data (no longer uses O2 data).
Anyways watching your short term and long term fuel trims should verify your lean condition. Some programs also have a "history" of codes and maybe some data before the CES sets which maybe helpful. U should be able to get a excel table for a current data run - again u can watch the BLM number to see when its closed loop and the BLM is changing. Dont bother to even look at the O2 numbers in closed loop. The lambda narrow band O2 sensor is constantly switching between 100mV and 900mV and unreadable (though the ECM is trending this data for BLM/short term fueling but to fast for u to make sense of it).
Anyways once u have Datamaster in use then try a realtime scan and post a table for us - i have no idea what Datamaster is goona look at or how to interpret it without seeing what it looks at.
Hope this helps.
However, since then have given the scanner back.
Thread Starter
Drifting
Joined: May 2007
Posts: 1,426
Likes: 165
From: Motor City
I had already re-toruqed them after a couple drives with the new headers, but checked last night and all were tight. Picking up some spark plug wires after work today and hopefully get them installed Friday. Also got the new pigtail connector for the o2 sensor yesterday in the mail.
Race Director
Joined: Mar 2015
Posts: 15,926
Likes: 579
I had already re-toruqed them after a couple drives with the new headers, but checked last night and all were tight. Picking up some spark plug wires after work today and hopefully get them installed Friday. Also got the new pigtail connector for the o2 sensor yesterday in the mail.
make sure they click twice. 
Thread Starter
Drifting
Joined: May 2007
Posts: 1,426
Likes: 165
From: Motor City
New wires installed and it runs noticeably smoother now
On initial startup, the car idled in the driveway for a few minutes and the CEL was triggered. However, I decided to give it a quick drive around the block and as soon as I pulled out of the driveway the CEL went off and fans shut down. Drove for close to an hr and it never came back.
Still havn't had time to get Datamaster installed and working, but that's next to check out whats going on with engine data. But at least im comfortable driving it now
Thanks to everyone who chimed in.
On initial startup, the car idled in the driveway for a few minutes and the CEL was triggered. However, I decided to give it a quick drive around the block and as soon as I pulled out of the driveway the CEL went off and fans shut down. Drove for close to an hr and it never came back.
Still havn't had time to get Datamaster installed and working, but that's next to check out whats going on with engine data. But at least im comfortable driving it now
Thanks to everyone who chimed in.