2G What's different from 98 and 99 Engine Bay Harness?

[PrimerPLus]

I am replacing my engine bay wiring harness (1998 GSX maual) to one from a (1999 GST Manual). I noticed that it does not have a couple of connections that mine had. Such as the Alternator Safety Relay MD128752.

Does anyone know if the 99's have this in a different location or just not at all? I assume if it doesn't have it, then it's not an issue. I also noticed that my 98 harness has a black one and a blue one of these connectors
but the 99 only has the blue

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and mine has this that connects evap purge solenoid to the ECU wiring harness but the 99 harness doesn't at least not in this location.

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Also no connection for Evap Purge Valve

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I know emissions items are not needed, but I like to keep mine.
Anyone does this changeout before? Will there be any issues, cels anything I need to change to make everything work correctly?
Thanks!

 

[luv2rallye]

The 99 blue connector in your first picture is the Engine Speed Detection Connector (note it's 2 wires MUST stay connected together for the coil 1-4 primary to connect to it's power transistor). The 95-98 instead has a Fuel Pump Check Connector here.

The Alternator Safety Relay MD128752 (aka alternator or generator relay) didn't come on all 99's (in fact it was totally eliminated on 2000 and later models). A Mitsubishi mechanic I talked to said it is not needed and was probably a cost savings thing that got done at the factory or post engineering which often doesn't show up in the manual.

The evap purge solenoid got moved around on the 98 and 99's. On my 99 GST it's down low on the driver side intake manifold.

Your last picture is not the Evap Purge Valve but rather the Evap Emission Vent Solenoid. It also moves around on the 98 and 99's. On my 99 GST it's next to the gas tank. On many AWD it's where your picture shows. However some have reported it's under the battery (some claim if have ABS). However it's always going to be close to the charcoal canister.

Attached are the engine wire harness configuration diagrams for the 1999 2.0L turbo (from the Mitsu factory service manual). Notice the Evap Emission Vent Solenoid is A-109 for AWD 2.0L turbo (which is under LF headlight). However it is E-61 (on interior harness) for both the FWD 2.0L turbo and 2.4L Spyder which is near the fuel tank. And it is E-62 for the NT also near the fuel tank. I suspect the harnesses have connectors for all of these so they can use the same harness in all these configurations..

 

[PrimerPLus]

Thanks for the info!