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**Gregski** · 08-31-2019, 08:20 AM

HP Tuners Section A) Disable the Oxygen Sensors (O2s)

In the First Series we took care of some housekeeping items such as disabling VATS, setting the Tach Signal for a V8, as well as inputting the correct Tire Size and Gear Ratio. Now in the Second Series we take on disabling all the codes that pertain to components that we chose to delete during the swap.

There are two schools of thought when it comes to LS Swaps and disabling the codes, some say drive the truck and see what codes it throws than research them a bit and if applicable, delete them. Nothing wrong with that method, but since I like to prep my PCM ahead of time before the engine even swallows a drop of gasoline, and especially since I know exactly what was deleted after all I deleted it, we might as well prevent those Codes from popping up ahead of time. Also and this may tip the scales, if you do your diligence and delete all the codes the best you can for the components you deleted than your MIL should not come on. However if it does, you should turn off the engine and look up the code rather than ignoring it assuming, eh it's probably for one of the items I deleted, and blindly press on with a glaring MIL. Hope you followed that logic.

So before we disable the secondary oxygen sensors, let's at least get the lingo right. We've all heard about the dreaded Engine Codes, but what are codes? Well essentially they are simply alerts.

When it comes to O2 sensors we may have heard the terms "Bank 1" or "Bank 2" what's a bank? I think of a bank as "Cylinder Head" and usually the cylinder head that has the #1 cylinder in it is Cylinder Head 1 (so in GM's case driver side) or "Bank 1" which by defualt makes "Bank 2" cylinder head 2 (aka passenger side in the GM world).

If we are thinking of the vehicle in terms of front to back as if we were following the exhaust flow, (leaks don't count, ha ha). Sensor 1 is the oxygen sensor in front of the catalytic converter (the cat) and Sensor 2 is behind the cat. And honsetly who knows where Sensor 3 lives/lived in my case it was already disabled? ha ha

Tunistas let's wrap our heads around these Oxygen Sensor codes as it may seem overwheling at first. Yes there may be 20 codes but there are only 5 conditions. Say what? only 5 things can happen, and here they are:

O2 Circuit Low Voltage

O2 Circuit High Voltage

O2 Circuit Slow Response

O2 Circuit No Acitivity Detected

O2 Heater Circuit

Now as you can see in the attached chart some conditions (such as O2 Circuit Slow Response) only happens on two sensors (and generates P0133 and P0153 codes) while other codes (such as O2 Heater Circuit) can happen on all six sensors (P0135, P0141, P0147, P0155, P0161, P0167).

If you look at the attached color coded chart I hope it helps you conceptualize what codes we will be nuking, all red codes get disabled.

Now let's look at the Black Magic that it takes to disable these codes, we have two controls:

SES Enable
Error Mode

If it was up to me I would break it up into a third control so it would look more like this:

SES (Enable / Disable)
MIL (MIL On First Error, MIL on Second Error, No MIL Light)
Report Code (On / Off)

1. Again we start in the comfort of our own home, we fire up our laptop and launch the Editor. Open the file we saved in Step 3 of Part III. (Our last saved file is always our starting point).

2. Make changes in the Editor, this time we will make changes only to the O2s that say "Sensor 2" regardless of what Bank they are on, these are the sensors behind the cat that we most likely deleted by thinning out the wiring harness. Refer to the colored chart attached or the cheat sheet below and Disable the SES on these and set the MIL to No Error Reported:

P0137 P0157

P0138 P0158

P0140 P0160

P0141 P0161

3. Save the changes you made to a new file and call it something like "04 - Disabled O2s"

4. Now you get to move the operation to your truck, hook up your HP Tuner to the OBDII port and then your USB cable to your laptop, turn the key to the ON position, launch the Editor program, and simply write the new changes to the PCM.

Note: sometimes you have to write the entire tune file to the PCM, sometimes it is perfectly happy with only writing what's changed, more on this later.

I promise you we will not Geek out this much for every batch of codes we delete, ie EGR, EVAP, Fuel Level, etc. This is our first batch so we are getting aquainted that's all.

More words with each pic:

08-31-2019, 08:20 AM	#49
Gregski Post Whore Join Date: Aug 2014 Location: Sacramento, CA Posts: 10,809	Re: HP Tuners Tutorials - Section A) Disable the Oxygen Sensors (O2s) HP Tuners Section A) Disable the Oxygen Sensors (O2s) In the First Series we took care of some housekeeping items such as disabling VATS, setting the Tach Signal for a V8, as well as inputting the correct Tire Size and Gear Ratio. Now in the Second Series we take on disabling all the codes that pertain to components that we chose to delete during the swap. There are two schools of thought when it comes to LS Swaps and disabling the codes, some say drive the truck and see what codes it throws than research them a bit and if applicable, delete them. Nothing wrong with that method, but since I like to prep my PCM ahead of time before the engine even swallows a drop of gasoline, and especially since I know exactly what was deleted after all I deleted it, we might as well prevent those Codes from popping up ahead of time. Also and this may tip the scales, if you do your diligence and delete all the codes the best you can for the components you deleted than your MIL should not come on. However if it does, you should turn off the engine and look up the code rather than ignoring it assuming, eh it's probably for one of the items I deleted, and blindly press on with a glaring MIL. Hope you followed that logic. So before we disable the secondary oxygen sensors, let's at least get the lingo right. We've all heard about the dreaded Engine Codes, but what are codes? Well essentially they are simply alerts. When it comes to O2 sensors we may have heard the terms "Bank 1" or "Bank 2" what's a bank? I think of a bank as "Cylinder Head" and usually the cylinder head that has the #1 cylinder in it is Cylinder Head 1 (so in GM's case driver side) or "Bank 1" which by defualt makes "Bank 2" cylinder head 2 (aka passenger side in the GM world). If we are thinking of the vehicle in terms of front to back as if we were following the exhaust flow, (leaks don't count, ha ha). Sensor 1 is the oxygen sensor in front of the catalytic converter (the cat) and Sensor 2 is behind the cat. And honsetly who knows where Sensor 3 lives/lived in my case it was already disabled? ha ha Tunistas let's wrap our heads around these Oxygen Sensor codes as it may seem overwheling at first. Yes there may be 20 codes but there are only 5 conditions. Say what? only 5 things can happen, and here they are: O2 Circuit Low Voltage O2 Circuit High Voltage O2 Circuit Slow Response O2 Circuit No Acitivity Detected O2 Heater Circuit Now as you can see in the attached chart some conditions (such as O2 Circuit Slow Response) only happens on two sensors (and generates P0133 and P0153 codes) while other codes (such as O2 Heater Circuit) can happen on all six sensors (P0135, P0141, P0147, P0155, P0161, P0167). If you look at the attached color coded chart I hope it helps you conceptualize what codes we will be nuking, all red codes get disabled. Now let's look at the Black Magic that it takes to disable these codes, we have two controls: SES Enable Error Mode If it was up to me I would break it up into a third control so it would look more like this: SES (Enable / Disable) MIL (MIL On First Error, MIL on Second Error, No MIL Light) Report Code (On / Off) 1. Again we start in the comfort of our own home, we fire up our laptop and launch the Editor. Open the file we saved in Step 3 of Part III. (Our last saved file is always our starting point). 2. Make changes in the Editor, this time we will make changes only to the O2s that say "Sensor 2" regardless of what Bank they are on, these are the sensors behind the cat that we most likely deleted by thinning out the wiring harness. Refer to the colored chart attached or the cheat sheet below and Disable the SES on these and set the MIL to No Error Reported: P0137 P0157 P0138 P0158 P0140 P0160 P0141 P0161 3. Save the changes you made to a new file and call it something like "04 - Disabled O2s" 4. Now you get to move the operation to your truck, hook up your HP Tuner to the OBDII port and then your USB cable to your laptop, turn the key to the ON position, launch the Editor program, and simply write the new changes to the PCM. Note: sometimes you have to write the entire tune file to the PCM, sometimes it is perfectly happy with only writing what's changed, more on this later. I promise you we will not Geek out this much for every batch of codes we delete, ie EGR, EVAP, Fuel Level, etc. This is our first batch so we are getting aquainted that's all. More words with each pic: Last edited by Gregski; 11-10-2019 at 05:49 AM.