98 engine harness swap to 99+
#1
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Hey all, I'm going to be swapping my 98 engine harness out at some point soon (I've been plagued with electrical issues since the harness got severed and was patched), and I'm wondering if I should just go with a 99 and later harness. I know I'll need a new sending unit for the fuel pump. I already have the gauge cluster and a 411 ecm. Does anyone know what other sensors I may need?
Thanks!
Thanks!
#2
Staging Lane
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I just did this more or less. It will require some re-pinning and adding of wires but not terrible overall: here is a quick rundown... feel free to pm me for more questions or do a search of my posts:
I would recommend keeping the 98 fuel system and 98 gauge cluster. Otherwise you would have to repin the cluster plug and possibly add wires... cant help you there. I used Frost on here for my tuning and we couldnt get the 99 fuel sending unit and 99 computer to read on the 98 gauges (I also had a missing wire I just resolved so that is not 100% proven)
1. The three plugs over the passenger fender well will need to be repined
2. The plugs behind the passenger side kick panel will need to be repinned and some splicing as the 98 dash harness has three plugs and the 99 has two.
3. Keep the 98 temperature sensor as it has three wires and hard wire a new wire from the third wire through the firewall to the plugs behind the kick panel to obtain functionality of the temperature gauge.
4. Run a wire from one of the fender well plugs to the passenger kick panel plugs to obtain tachometer (forget which plugs and wires at the moment)
5. Add a wire to the C2 red 38 position on the 99 pcm and run it to the C210 F spot on the kick panel plug to get gas gauge functionality. You will need to have a tuner or someone do the segment swap to get the 99 pcm to read the 98 sending unit.
I think that is basically the rundown. Obviously the specific repins aren't listed. I can help you with that but my notes are all hand written not in front of me at the moment.
I would recommend keeping the 98 fuel system and 98 gauge cluster. Otherwise you would have to repin the cluster plug and possibly add wires... cant help you there. I used Frost on here for my tuning and we couldnt get the 99 fuel sending unit and 99 computer to read on the 98 gauges (I also had a missing wire I just resolved so that is not 100% proven)
1. The three plugs over the passenger fender well will need to be repined
2. The plugs behind the passenger side kick panel will need to be repinned and some splicing as the 98 dash harness has three plugs and the 99 has two.
3. Keep the 98 temperature sensor as it has three wires and hard wire a new wire from the third wire through the firewall to the plugs behind the kick panel to obtain functionality of the temperature gauge.
4. Run a wire from one of the fender well plugs to the passenger kick panel plugs to obtain tachometer (forget which plugs and wires at the moment)
5. Add a wire to the C2 red 38 position on the 99 pcm and run it to the C210 F spot on the kick panel plug to get gas gauge functionality. You will need to have a tuner or someone do the segment swap to get the 99 pcm to read the 98 sending unit.
I think that is basically the rundown. Obviously the specific repins aren't listed. I can help you with that but my notes are all hand written not in front of me at the moment.
#3
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I just did this more or less. It will require some re-pinning and adding of wires but not terrible overall: here is a quick rundown... feel free to pm me for more questions or do a search of my posts:
I would recommend keeping the 98 fuel system and 98 gauge cluster. Otherwise you would have to repin the cluster plug and possibly add wires... cant help you there. I used Frost on here for my tuning and we couldnt get the 99 fuel sending unit and 99 computer to read on the 98 gauges (I also had a missing wire I just resolved so that is not 100% proven)
1. The three plugs over the passenger fender well will need to be repined
2. The plugs behind the passenger side kick panel will need to be repinned and some splicing as the 98 dash harness has three plugs and the 99 has two.
3. Keep the 98 temperature sensor as it has three wires and hard wire a new wire from the third wire through the firewall to the plugs behind the kick panel to obtain functionality of the temperature gauge.
4. Run a wire from one of the fender well plugs to the passenger kick panel plugs to obtain tachometer (forget which plugs and wires at the moment)
5. Add a wire to the C2 red 38 position on the 99 pcm and run it to the C210 F spot on the kick panel plug to get gas gauge functionality. You will need to have a tuner or someone do the segment swap to get the 99 pcm to read the 98 sending unit.
I think that is basically the rundown. Obviously the specific repins aren't listed. I can help you with that but my notes are all hand written not in front of me at the moment.
I would recommend keeping the 98 fuel system and 98 gauge cluster. Otherwise you would have to repin the cluster plug and possibly add wires... cant help you there. I used Frost on here for my tuning and we couldnt get the 99 fuel sending unit and 99 computer to read on the 98 gauges (I also had a missing wire I just resolved so that is not 100% proven)
1. The three plugs over the passenger fender well will need to be repined
2. The plugs behind the passenger side kick panel will need to be repinned and some splicing as the 98 dash harness has three plugs and the 99 has two.
3. Keep the 98 temperature sensor as it has three wires and hard wire a new wire from the third wire through the firewall to the plugs behind the kick panel to obtain functionality of the temperature gauge.
4. Run a wire from one of the fender well plugs to the passenger kick panel plugs to obtain tachometer (forget which plugs and wires at the moment)
5. Add a wire to the C2 red 38 position on the 99 pcm and run it to the C210 F spot on the kick panel plug to get gas gauge functionality. You will need to have a tuner or someone do the segment swap to get the 99 pcm to read the 98 sending unit.
I think that is basically the rundown. Obviously the specific repins aren't listed. I can help you with that but my notes are all hand written not in front of me at the moment.
#4