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You also said "I’m running long tube headers going to have to extend plugs for o2." Just so we are on the same page-you CANNOT, and MUST NOT cut the wires between the sensor and the sensor connector. If you need to extend wiring due to the L/T headers, you MUST do this on the harness side. O2 sensors use the wiring between their connector, and the actual sensor, to get oxygen from between the wires. Cutting the wires between sensor & connector destroys the sensor! I think, from what you posted, that your plan was to extend the harness, I just want to be certain that this is what you end up doing.
Hang in there. You are very close to being done! Your wiring for the O2 sensors is going to require a ground to engine block, or frame, and a 12V+ switched source (Pink wires), and then the other 2 wires go back to the PCM. If you look at the way the factory wiring has it set up, the MAF sensor and all 4 O2 sensors shared a common power supply circuit. Meaning, they were all on the same fuse. If that fuse popped due to a bad heater in one of the O2's, the MAF would then start setting codes. For simplicity, I followed GM's lead and ran my 2 O2's, and my MAF to their own fuse in my stand alone harness.
You know we expect you to post a video when it's up and running right? We all have to hear the smooth rumble of that engine after all of your hard work.
You also said "I’m running long tube headers going to have to extend plugs for o2." Just so we are on the same page-you CANNOT, and MUST NOT cut the wires between the sensor and the sensor connector. If you need to extend wiring due to the L/T headers, you MUST do this on the harness side. O2 sensors use the wiring between their connector, and the actual sensor, to get oxygen from between the wires. Cutting the wires between sensor & connector destroys the sensor! I think, from what you posted, that your plan was to extend the harness, I just want to be certain that this is what you end up doing.
Hang in there. You are very close to being done! Your wiring for the O2 sensors is going to require a ground to engine block, or frame, and a 12V+ switched source (Pink wires), and then the other 2 wires go back to the PCM. If you look at the way the factory wiring has it set up, the MAF sensor and all 4 O2 sensors shared a common power supply circuit. Meaning, they were all on the same fuse. If that fuse popped due to a bad heater in one of the O2's, the MAF would then start setting codes. For simplicity, I followed GM's lead and ran my 2 O2's, and my MAF to their own fuse in my stand alone harness.
You know we expect you to post a video when it's up and running right? We all have to hear the smooth rumble of that engine after all of your hard work.
I had already cut the wires from one of the o2 plugs from the harness I’m soldering it back on. It should be fine right ?
Ok yes I saw the pink wires I’m going to have to get help figuring out the fuse block part also I almost wanted to just run a stock Camaro fuse block or something but I want it to be nice & clean since I’m already going through all this hassle.
yes of course I’m posting it up once I’m done I’m getting ready to pull this 305 out right now. 👍
as G.Astma mentioned above you will need BOTH O2 sensors-1 for bank 1, and the other for Bank 2. You MUST run both front O2 sensors!
TPS connections BLUE 46 GRAY TPS 5V reference, BLUE 54 BLACK TPS Sensor GROUND, RED 24 TPS Signal
IAC connections RED 76, RED 77, RED 78, RED 79, if there is an extra wire, and it is BLACK in color, it's a ground!
For BOTH front O2 sensors, you will need the FLAT connectors as you have pictured. The square connector is for the REAR, or AFTER-CAT O2 sensor. If you can't find the other missing O2 connector, look in the transmission wiring harness side as the other 2 O2 connectors will be tied in with the transmission harness. On the trucks, bank 1 O2's (both front & rear) are tied in with the transmission wiring harness. Since you have a Corvette harness, I suspect your harness was different. Still, you should have 2 flat O2 connectors somewhere in the harness. Just need to find it, root it out, and wire it up.
as G.Astma mentioned above you will need BOTH O2 sensors-1 for bank 1, and the other for Bank 2. You MUST run both front O2 sensors!
TPS connections BLUE 46 GRAY TPS 5V reference, BLUE 54 BLACK TPS Sensor GROUND, RED 24 TPS Signal
IAC connections RED 76, RED 77, RED 78, RED 79, if there is an extra wire, and it is BLACK in color, it's a ground!
For BOTH front O2 sensors, you will need the FLAT connectors as you have pictured. The square connector is for the REAR, or AFTER-CAT O2 sensor. If you can't find the other missing O2 connector, look in the transmission wiring harness side as the other 2 O2 connectors will be tied in with the transmission harness. On the trucks, bank 1 O2's (both front & rear) are tied in with the transmission wiring harness. Since you have a Corvette harness, I suspect your harness was different. Still, you should have 2 flat O2 connectors somewhere in the harness. Just need to find it, root it out, and wire it up.
perfect I have it completely labeled now.
my harness must not of had the IAC sensor connection or it may have been different so I have to get one to pin it in.
I had a flat style plug left over with 6 pins that didn’t go anywhere or showed on the sheet so I cut it off. I’ll post a picture of where this 6 pin plug led to.
The IAC I’m guessing is the sensor above the TPS on the TB ?
my harness must not of had the IAC sensor connection or it may have been different so I have to get one to pin it in.
I had a flat style plug left over with 6 pins that didn’t go anywhere or showed on the sheet so I cut it off. I’ll post a picture of where this 6 pin plug led to.
The IAC I’m guessing is the sensor above the TPS on the TB ?
your harness is the corvette drive by WIRE harness while your throttle body is drive by CABLE, so the connectors are different. I initially started my 5.3 swapped '72 c10 with drive by wire and could not get it to work for the life of me, so I went to the local lkq and took alll the throttle body wiring off of a 2001 Silverado and converted to cable throttle. This was no big deal since I already had a 2001 Yukon red/blue pcm. Long story short: as long as you have a RED/BLUE PCM then in my opinion, your best option is to convert it to drive by CABLE using throttle body wiring off of a 99-02 Silverado. Also, your tuner will have to change your tune for this. Seems like you could flash yours with a stock 4.8 truck tune and go from there. It isn't that hard to swap it over, I built my harness at 16 and I will agree with kawabuggy that it seems very intimidating to begin with, but it isn't as bad once you do it a time or two.
Went down to my local pick n pull today got all the plugs I needed.
IAC plug
MAF plug (though I may have grabbed the wrong one)
OBD2 plug
3 wire engine temp sensor & plug from a Camaro since I’m using my original gauges
Oil pressure plug I want to run this also
I just need to pin them in the harness run the wires & figure out the fuse block portion of this harness rewire. If you have a Fry’s electronics near you I found rolls of loom for around $5 bucks vs auto parts stores charging $30+
I am very pleased & excited with all the help I am receiving I can’t wait to have the Mali ready!
Went down to my local pick n pull today got all the plugs I needed.
IAC plug
MAF plug (though I may have grabbed the wrong one)
OBD2 plug
3 wire engine temp sensor & plug from a Camaro since I’m using my original gauges
Oil pressure plug I want to run this also
I just need to pin them in the harness run the wires & figure out the fuse block portion of this harness rewire. If you have a Fry’s electronics near you I found rolls of loom for around $5 bucks vs auto parts stores charging $30+
I am very pleased & excited with all the help I am receiving I can’t wait to have the Mali ready!
mechanical fuel pump.. Th-350.. Yes, those were the days! You pulled the whole front end of the car off. Makes it so much easier when doing swaps like this. Good work!
mechanical fuel pump.. Th-350.. Yes, those were the days! You pulled the whole front end of the car off. Makes it so much easier when doing swaps like this. Good work!
thank you very much I appreciate the help & encouragement!
Been busy cleaning up & painting frame. I want my whole engine bay to look good when I drop the engine in. Firewall is next then I will be ready to drop engine in!
Harness is pinned in I just need to extend a couple connections & figure out fuse block! ✅
Repinning IAC plug you told me the PIN numbers but I don’t know which ones go to the plug itself I have two green with white stripe & two green with black stripe anyone ?
RED 76 LT. GREEN/WHITE IAC COIL B HIGH
RED 77 LT. GREEN/BLACK IAC COIL B LOW
RED 78 LT. BLUE/BLACK IAC COIL A LOW
RED 79 LT. BLUE/WHITE IAC COIL A HIGH
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