I need help on 4.8 ls harness
Thread Starter
Teching In
Joined: Jan 2019
Posts: 4
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I need help on 4.8 ls harness I have a donor 4.8 Vortec ls out of a 2000 Sierra. I’m swapping it to a 89 k1500. My question is when I swap the harness over can I just plug in the sensors I’m going to use and drive it like that or is taking the plugs off that I’m not using a must? Its only temporary for a couple of months until I turbo it and have one made. I’m new to running wiring harnesses In general so please help lol
TECH Fanatic
Joined: Dec 2017
Posts: 1,467
Likes: 265
From: Bossier City, Louisiana
Also, don't forget - as a minimum, the Vehicle Anti Theft System (VATS) inside the 2000 Sierra powertrain control module must be disabled by somebody savvy with HP Tuners or similar. The engine will not start unless VATS is disabled.
Yes, the check engine light will also be on unless your HP Tuners guy disables the warnings for things like EGR and EVAP while he is inside your tune disabling VATS. The following is everything I had done to the software inside my PCM:
Startup and at temp Idle Raised 100 rpm
PE Delay set to zero - Power Enrichment
Cat Overtemp Disabled
All EVAP, EGR, Fuel Sender, and Rear O2 codes deleted
Speedo and shift points corrected for current tire/gear
Max line psi disabled in case of MAF failure
VATS turned off
Fans Activate - First fan on @ 195, second on at 210, both off at 190
Rick
Yes, the check engine light will also be on unless your HP Tuners guy disables the warnings for things like EGR and EVAP while he is inside your tune disabling VATS. The following is everything I had done to the software inside my PCM:
Startup and at temp Idle Raised 100 rpm
PE Delay set to zero - Power Enrichment
Cat Overtemp Disabled
All EVAP, EGR, Fuel Sender, and Rear O2 codes deleted
Speedo and shift points corrected for current tire/gear
Max line psi disabled in case of MAF failure
VATS turned off
Fans Activate - First fan on @ 195, second on at 210, both off at 190
Rick
Thread Starter
Teching In
Joined: Jan 2019
Posts: 4
Likes: 0
Also, don't forget - as a minimum, the Vehicle Anti Theft System (VATS) inside the 2000 Sierra powertrain control module must be disabled by somebody savvy with HP Tuners or similar. The engine will not start unless VATS is disabled.
Yes, the check engine light will also be on unless your HP Tuners guy disables the warnings for things like EGR and EVAP while he is inside your tune disabling VATS. The following is everything I had done to the software inside my PCM:
Startup and at temp Idle Raised 100 rpm
PE Delay set to zero - Power Enrichment
Cat Overtemp Disabled
All EVAP, EGR, Fuel Sender, and Rear O2 codes deleted
Speedo and shift points corrected for current tire/gear
Max line psi disabled in case of MAF failure
VATS turned off
Fans Activate - First fan on @ 195, second on at 210, both off at 190
Rick
Yes, the check engine light will also be on unless your HP Tuners guy disables the warnings for things like EGR and EVAP while he is inside your tune disabling VATS. The following is everything I had done to the software inside my PCM:
Startup and at temp Idle Raised 100 rpm
PE Delay set to zero - Power Enrichment
Cat Overtemp Disabled
All EVAP, EGR, Fuel Sender, and Rear O2 codes deleted
Speedo and shift points corrected for current tire/gear
Max line psi disabled in case of MAF failure
VATS turned off
Fans Activate - First fan on @ 195, second on at 210, both off at 190
Rick
TECH Fanatic
Joined: Dec 2017
Posts: 1,467
Likes: 265
From: Bossier City, Louisiana
There are vendors here on the site that you can send your PCM to and they will make the required changes - its called a "mail order tune". You can also learn a lot about your wiring by visiting the site known as LT1Swap.
Rick
Rick
