5.3 harness rewire
#21
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The tall black sensor at the back of the engine is OIL PRESSURE SENDING UNIT.
If you are NOT going to run a factory dash that has the DIC (driver information center) then you don't need to run the OIL LEVEL SENDING unit on the side of the oil pan under the starter. My understanding is that the OIL LEVEL sender then signals the PCM to send the message to the DIC "low oil level". If you don't have an interface, or a DIC, then there is no point in having the Oil level sending unit at all. I deleted mine on the 70 truck. I actually ground the threads out of the hole and put in a rubber expandable plug, and then painted over it. You could just as easily leave the factory unit in place with no connector on it.
The last picture the big round connector IS for an automatic transmission. Since the harness is from a 'vette it would have to be a 4L60E (all that the vettes used in 2001). I bet that wiring is REALLY long! The trans in the 'Vette is all the way back at the rear of the car.. Those other 2 round connectors with the trans connector-I have no clue what those are.
Yes, the picture you posted with the O2 sensor connectors is just that-O2 connectors! The FLAT connectors are the FRONT O2's, and the square ones are for the after-cat O2's. At least this is how it is on the truck harnesses.
If you find a connector that you are not sure what it is, use your continuity tester, or DVM, and probe one of the pins in the connector and then use the other probe and just run it along all of the pins (once you remove the plastic cover) and listen for continuity. Then, use your pin out sheet at LT1swap.com to identify the connector.
If you are NOT going to run a factory dash that has the DIC (driver information center) then you don't need to run the OIL LEVEL SENDING unit on the side of the oil pan under the starter. My understanding is that the OIL LEVEL sender then signals the PCM to send the message to the DIC "low oil level". If you don't have an interface, or a DIC, then there is no point in having the Oil level sending unit at all. I deleted mine on the 70 truck. I actually ground the threads out of the hole and put in a rubber expandable plug, and then painted over it. You could just as easily leave the factory unit in place with no connector on it.
The last picture the big round connector IS for an automatic transmission. Since the harness is from a 'vette it would have to be a 4L60E (all that the vettes used in 2001). I bet that wiring is REALLY long! The trans in the 'Vette is all the way back at the rear of the car.. Those other 2 round connectors with the trans connector-I have no clue what those are.
Yes, the picture you posted with the O2 sensor connectors is just that-O2 connectors! The FLAT connectors are the FRONT O2's, and the square ones are for the after-cat O2's. At least this is how it is on the truck harnesses.
If you find a connector that you are not sure what it is, use your continuity tester, or DVM, and probe one of the pins in the connector and then use the other probe and just run it along all of the pins (once you remove the plastic cover) and listen for continuity. Then, use your pin out sheet at LT1swap.com to identify the connector.
#22
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The tall black sensor at the back of the engine is OIL PRESSURE SENDING UNIT.
If you are NOT going to run a factory dash that has the DIC (driver information center) then you don't need to run the OIL LEVEL SENDING unit on the side of the oil pan under the starter. My understanding is that the OIL LEVEL sender then signals the PCM to send the message to the DIC "low oil level". If you don't have an interface, or a DIC, then there is no point in having the Oil level sending unit at all. I deleted mine on the 70 truck. I actually ground the threads out of the hole and put in a rubber expandable plug, and then painted over it. You could just as easily leave the factory unit in place with no connector on it.
The last picture the big round connector IS for an automatic transmission. Since the harness is from a 'vette it would have to be a 4L60E (all that the vettes used in 2001). I bet that wiring is REALLY long! The trans in the 'Vette is all the way back at the rear of the car.. Those other 2 round connectors with the trans connector-I have no clue what those are.
Yes, the picture you posted with the O2 sensor connectors is just that-O2 connectors! The FLAT connectors are the FRONT O2's, and the square ones are for the after-cat O2's. At least this is how it is on the truck harnesses.
If you find a connector that you are not sure what it is, use your continuity tester, or DVM, and probe one of the pins in the connector and then use the other probe and just run it along all of the pins (once you remove the plastic cover) and listen for continuity. Then, use your pin out sheet at LT1swap.com to identify the connector.
If you are NOT going to run a factory dash that has the DIC (driver information center) then you don't need to run the OIL LEVEL SENDING unit on the side of the oil pan under the starter. My understanding is that the OIL LEVEL sender then signals the PCM to send the message to the DIC "low oil level". If you don't have an interface, or a DIC, then there is no point in having the Oil level sending unit at all. I deleted mine on the 70 truck. I actually ground the threads out of the hole and put in a rubber expandable plug, and then painted over it. You could just as easily leave the factory unit in place with no connector on it.
The last picture the big round connector IS for an automatic transmission. Since the harness is from a 'vette it would have to be a 4L60E (all that the vettes used in 2001). I bet that wiring is REALLY long! The trans in the 'Vette is all the way back at the rear of the car.. Those other 2 round connectors with the trans connector-I have no clue what those are.
Yes, the picture you posted with the O2 sensor connectors is just that-O2 connectors! The FLAT connectors are the FRONT O2's, and the square ones are for the after-cat O2's. At least this is how it is on the truck harnesses.
If you find a connector that you are not sure what it is, use your continuity tester, or DVM, and probe one of the pins in the connector and then use the other probe and just run it along all of the pins (once you remove the plastic cover) and listen for continuity. Then, use your pin out sheet at LT1swap.com to identify the connector.
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#28
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If you are running SD, then I see no reason to utilize the MAF sensor wiring. I think-THOUGH I COULD BE WRONG-that you should still utilize the IAT sensor. The EARLIER vehicles used an IAT that is separate from the MAF. I have read on the forums that guys-when running MAF-less---that they buy the earlier IAT sensor, and plug it in into the air intake tract. The computer can still use that sensor information to help control fueling under varying temperatures. I've never set one up to run without a MAF so maybe post over in the "TUNING" section and ask the question there. I would hate to be giving you bad information and create problems for you.
If it were my vehicle, I would leave the oil pressure sending unit hooked up. If ever you data log with HP Tuners you can easily see your oil pressure in that manner, or even with a traditional scanner. It would make diagnosing future problems much easier to have that data available. I would think.
I see you have your gas tank vent purge solenoid laying on top of the engine.. Is that something you are wanting to re-use? I deleted that from my vehicle as I do not have to go through emissions. Maybe you need it?
Also, before I forget, you are doing an AWESOME job!!!! Kudos to you for tackling this. It might have seemed stressful at first, but I think even you would agree that once you have played with it a while, the fear kind of subsides and then it's just another task to get done.
If it were my vehicle, I would leave the oil pressure sending unit hooked up. If ever you data log with HP Tuners you can easily see your oil pressure in that manner, or even with a traditional scanner. It would make diagnosing future problems much easier to have that data available. I would think.
I see you have your gas tank vent purge solenoid laying on top of the engine.. Is that something you are wanting to re-use? I deleted that from my vehicle as I do not have to go through emissions. Maybe you need it?
Also, before I forget, you are doing an AWESOME job!!!! Kudos to you for tackling this. It might have seemed stressful at first, but I think even you would agree that once you have played with it a while, the fear kind of subsides and then it's just another task to get done.
Last edited by Kawabuggy; 09-01-2018 at 03:37 PM.
#29
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If you are running SD, then I see no reason to utilize the MAF sensor wiring. I think-THOUGH I COULD BE WRONG-that you should still utilize the IAT sensor. The EARLIER vehicles used an IAT that is separate from the MAF. I have read on the forums that guys-when running MAF-less---that they buy the earlier IAT sensor, and plug it in into the air intake tract. The computer can still use that sensor information to help control fueling under varying temperatures. I've never set one up to run without a MAF so maybe post over in the "TUNING" section and ask the question there. I would hate to be giving you bad information and create problems for you.
If it were my vehicle, I would leave the oil pressure sending unit hooked up. If ever you data log with HP Tuners you can easily see your oil pressure in that manner, or even with a traditional scanner. It would make diagnosing future problems much easier to have that data available. I would think.
I see you have your gas tank vent purge solenoid laying on top of the engine.. Is that something you are wanting to re-use? I deleted that from my vehicle as I do not have to go through emissions. Maybe you need it?
Also, before I forget, you are doing an AWESOME job!!!! Kudos to you for tackling this. It might have seemed stressful at first, but I think even you would agree that once you have played with it a while, the fear kind of subsides and then it's just another task to get done.
If it were my vehicle, I would leave the oil pressure sending unit hooked up. If ever you data log with HP Tuners you can easily see your oil pressure in that manner, or even with a traditional scanner. It would make diagnosing future problems much easier to have that data available. I would think.
I see you have your gas tank vent purge solenoid laying on top of the engine.. Is that something you are wanting to re-use? I deleted that from my vehicle as I do not have to go through emissions. Maybe you need it?
Also, before I forget, you are doing an AWESOME job!!!! Kudos to you for tackling this. It might have seemed stressful at first, but I think even you would agree that once you have played with it a while, the fear kind of subsides and then it's just another task to get done.
damnit I already cut the iat sensor I will post in tuning to get a second opinion. MAF is gone also but I will double check as well.
What do do you mean sd?
Not using the gas vent vent purge everything is deleted I finished cleaning up the harness yesterday it’s basically injectors, coils & a couple sensors left no o2 nothing.
not worried about emissions have a place for smog.
thank you I appreciate your help I honestly wouldn’t have tackled it without your assistance!!!
#30
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SD = Speed Density, which you use when you don't use MAF
#32
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If you deleted your MAF, and O2 sensors, you have NO CHOICE but to run OLSD. (Open-Loop Speed Density). Is there a reason you did not want to use the O2's and MAF????? Are you turbo'ing the vehicle, or super charging it? Track only car?
If this is a street driven car, and the engine has a cam that is not super radical, there really is no good reason to NOT use the MAF, and O2 sensors... The MAF & O2 sensors (with a GOOD TUNE) can make the car super reliable in changing weather, and temperature, conditions. Whereas an OLSD tune is going to need to be constantly updated, or changed, depending on quality of gas, temperature, barometric pressure, and a bunch of other things that will factor in to engine volumetric efficiency. If it's a race car, then those guys just EXPECT to have to tune, or re-tune, the vehicle every time they race.
If this vehicle is something you want to jump in every day, hit the key and drive off without having to worry about flashing a new tune, and you want RELIABILITY... Then you need to retain the O2's and the MAF... Did someone tell you that you should not be running those things?
If this is a street driven car, and the engine has a cam that is not super radical, there really is no good reason to NOT use the MAF, and O2 sensors... The MAF & O2 sensors (with a GOOD TUNE) can make the car super reliable in changing weather, and temperature, conditions. Whereas an OLSD tune is going to need to be constantly updated, or changed, depending on quality of gas, temperature, barometric pressure, and a bunch of other things that will factor in to engine volumetric efficiency. If it's a race car, then those guys just EXPECT to have to tune, or re-tune, the vehicle every time they race.
If this vehicle is something you want to jump in every day, hit the key and drive off without having to worry about flashing a new tune, and you want RELIABILITY... Then you need to retain the O2's and the MAF... Did someone tell you that you should not be running those things?
#33
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If you deleted your MAF, and O2 sensors, you have NO CHOICE but to run OLSD. (Open-Loop Speed Density). Is there a reason you did not want to use the O2's and MAF????? Are you turbo'ing the vehicle, or super charging it? Track only car?
If this is a street driven car, and the engine has a cam that is not super radical, there really is no good reason to NOT use the MAF, and O2 sensors... The MAF & O2 sensors (with a GOOD TUNE) can make the car super reliable in changing weather, and temperature, conditions. Whereas an OLSD tune is going to need to be constantly updated, or changed, depending on quality of gas, temperature, barometric pressure, and a bunch of other things that will factor in to engine volumetric efficiency. If it's a race car, then those guys just EXPECT to have to tune, or re-tune, the vehicle every time they race.
If this vehicle is something you want to jump in every day, hit the key and drive off without having to worry about flashing a new tune, and you want RELIABILITY... Then you need to retain the O2's and the MAF... Did someone tell you that you should not be running those things?
If this is a street driven car, and the engine has a cam that is not super radical, there really is no good reason to NOT use the MAF, and O2 sensors... The MAF & O2 sensors (with a GOOD TUNE) can make the car super reliable in changing weather, and temperature, conditions. Whereas an OLSD tune is going to need to be constantly updated, or changed, depending on quality of gas, temperature, barometric pressure, and a bunch of other things that will factor in to engine volumetric efficiency. If it's a race car, then those guys just EXPECT to have to tune, or re-tune, the vehicle every time they race.
If this vehicle is something you want to jump in every day, hit the key and drive off without having to worry about flashing a new tune, and you want RELIABILITY... Then you need to retain the O2's and the MAF... Did someone tell you that you should not be running those things?
i kind of just got irritated when I had the harness stripped & pulled the MAF & o2 off I may have left 1 o2 sensor still in harness.
so moving forward I need to repin iat, MAF & o2 sensors back in harness I will have to look at pin out to figure out where to redo them...
#34
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I think you will be very happy that you put those sensors back in the car! Yes, it's a little more wiring, but you've made it this far, I'm certain you won't have any issue getting those pieces wired back in.
#35
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i will I’ll figure it out you’ve been a lot of help I have time to work on it tomorrow.
Do I absolutely need to run both o2 or is 1 fine ? I’m running long tube headers going to have to extend plugs for o2.
#36
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Run both so both banks are covered.
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#38
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Whichever is the front sensor is the one you use for both banks
#40
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