4.3 TBI to 5.0 TBI question

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Matt Conner

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Which ECM do you have? Pull the glovebox and slide the ECM to the left, it's held in place by spring clips on the left side and guide pins on the right. You'll need to disconnect the 2 wire looms (squeeze the blue clips) to remove it and, if it's still stock you should be able to see the Service number label. Then you can remove the cover (2 screws) and look to see what BCC you have. The picture on the right should be like yours.

http://www.gearhead-efi.com/BCCFind/

Here's one of mine with a ZIF (Zero Insertion Force) socket conversion so I can flash my own chips.

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This is the ECM i have
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Matt Conner

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Can I swap this ECM to a 7747 or can I put the eprom in the 4288 ECM for the 5.0l 5 speed, or do I need the 7747 ECM?
 

PlayingWithTBI

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According to this chart your ECM is for a 91-92 S10, C/K truck (close enough). The 7747 should work (you'll have to compare pin-outs to be sure).

https://xtronics.com/wiki/GM_ECU_eproms.html

Here's BCC antz8364 I found on this website which is set for 8cylinder and manual trans. Not sure if it's for the 5.7L though. You'll have to do some homework, maybe dave w among others there can help, you can join and ask if anyone has a chip for a 7747 and a 5.7L with manual trans.

http://www.gearhead-efi.com/gearhead-efi/bin/1227747/l19/
 

Matt Conner

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According to this chart your ECM is for a 91-92 S10, C/K truck (close enough). The 7747 should work (you'll have to compare pin-outs to be sure.
https://xtronics.com/wiki/GM_ECU_eproms.html

Here's BCC antz8364 I found on this website which is set for 8cylinder and manual trans. Not sure if it's for the 5.7L though. You'll have to do some homework, maybe dave w among others there can help, you can join and ask if anyone has a chip for a 7747 and a 5.7L with manual trans.

http://www.gearhead-efi.com/gearhead-efi/bin/1227747/l19/
So I can Buy a 7747 and put a prom chip for a 305 (5.0) and it’s plug and play?
 

Matt Conner

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Pretty much although it's always better to data log and tune, you can get better mileage and performance with tuning.
I’ve read about repinning the ECM, will I have to do that or can I just put a prom in it and plug it in and go? I’m not concerned about the proformance, I just want my truck back and runnin
 

Matt Conner

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Which ECM do you have? Pull the glovebox and slide the ECM to the left, it's held in place by spring clips on the left side and guide pins on the right. You'll need to disconnect the 2 wire looms (squeeze the blue clips) to remove it and, if it's still stock you should be able to see the Service number label. Then you can remove the cover (2 screws) and look to see what BCC you have. The picture on the right should be like yours.

http://www.gearhead-efi.com/BCCFind/

Here's one of mine with a ZIF (Zero Insertion Force) socket conversion so I can flash my own chips.

You must be registered for see images attach

I have a question on what this is,
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PlayingWithTBI

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ESC (Electronic Spark Control) for Knock Sensor in front, and MAP (Manifold Absolute Pressure) sensor in the back. To the left (passenger's side of bracket) is your EGR (Exhaust Gas Recirculating) solenoid. To the right mounted on the throttle body is your TPS (Throttle Position Sensor), behind it, also mounted on the throttle body is your IAC (Intake Air Control) valve
 

PlayingWithTBI

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I’ve read about repinning the ECM, will I have to do that or can I just put a prom in it and plug it in and go? I’m not concerned about the proformance, I just want my truck back and runnin
I'm not positive (usual disclaimer) but I think it will hook right up to the same year model, IIRC 87 - 91 are all the same.
 
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