EsKay

I know someone selling a 1jz with harness from a 93 sc300 and was thinking about purchasing it. Will this be a plug and play transfer? Or will I have to do modifications to the harness because it's coming from an OBD1 SC? Also the 1st gen MAPECU is wired into the harness.. will that cause any additional issues?

Thanks in advance!

pogoism9

iTrader: (1)

You would need to not use any of the existing wiring. Your ECU wont work with an obd2 system. You can bypass it with some heavy wiring work, or swap out the entire dash harness and whatnot. The other option is to go standalone.

Ali SC3

iTrader: (10)

its really doesn't matter if the car is obd1 or obd2 unless you are expecting the obd2 port to work which it wont cause 1jz ecu is obd1 and jdm.

As long as the 97 SC has the same body plugs as the earlier SC's then it should be fine. the harness really only plugs into the car at the body plugs, and at the fusebox.

I would guess the body plugs on a 97 are the same or similar since its non vvti and has the same ecu connector as obd1 92-95. Its possible they changed it some but I doubt it. there should be threads regarding body plug difference on the different years, that is what you need to look up if its the same it will work fine.

Pogoism, do you actually know what needs to be bypassed with some heavy work because that doesnt sound right at all. I know there is only 1-2 wires different between obd1 and obd2, and that is just for the obd2 port, so when using an obd1 ecu in an obd2 chassis you don't have to do any changes as long as the harness plugs into the body plugs by the ecu. its actually pretty easy to go between obd1 and obd2. the obd2 port wont work but the car will drive and work just fine like an obd1 would, and you can still use the CEL to pull check engine light codes.

pogoism9

iTrader: (1)

It could be that easy. I do know that 96 and 97 cars are their own monster. I know with the 400 there are a few 96-97 only parts.

Im no expert on jz swaps but I know enough about these cars to know that nothing is as easy as it seems. Your mileage may vary. Particularly on 96-97 cars.

Im currently in the process of swapping a 99 vvti UZ into my 95 and I can tell you that its not a walk in the park electronically

Ali SC3

iTrader: (10)

I thought all sc300 and sc400 have the same body plugs but I don't know 100% for originally vvti cars 98+, non vvti I know they are the same body plugs and are the same as found on a soarer 1jz harness.

now the number of wires sticking out of them may be more on the 400, but they are the same plugs. usually the body plugs are unique to a given chassis, which is why a soarer harness normally plugs into a sc chassis when you extend it about a foot. a 1jz harness for a SC means it has body plugs for an SC, with me so far?

are you saying that the body plugs are different on the 99 sc400 vs your 95 sc400 cause that would be odd, I guess they could have been a vvti thing but I think they should be the same or similar. you should use the whole 99 motor and engine harness. the only thing you would need to do is sort out any wire difference on the body plugs themselves if they are the same, and add a few wires for the obd2 port IF you even want an obd2 port.

the 2jzge didn't really change from 92-97, it stayed non vvti, and there were only a couple changes on the main engine harness (2nd crank sensor on 96-97). when you change the engine harness though none of that matters it just matter that the new harness has the correct body plugs. being from a soarer and made to work for an SC already it should have the same body plugs and plug in to an SC chassis.

as I said earlier, for example on a supra turbo you can plug in the obd2 ecu on an obd1 harness and with no other changes it will run the motor properly. it only takes another wire and the existing wires from the obdd1 port to wire up an obd2 port. so when you say obd2 system, really its only another wire and a plug and the right ecu, so it has nothing to do with the dash and rest of the car u7nless you want to replace the whole dash harness vs adding 1 wire and a plug (would be a waste of time and totally unnecessary). maybe if you need some help with your v8 conversion then post a thread and I can try and help out where needed.

according to this thread it plugs right in
https://www.clublexus.com/forums/sc-...c300-help.html

Vrank

iTrader: (4)

Just make sure you use the alternator plug that is in your chassis. The 93 harness should have one built into it, but it will not work. IIRC 95 all sc retained alternator wiring in the chassis side of things. Before that it was just the 400s.

EsKay

Thanks for the info guys!

I did a whole bunch of searching and all I could come up with was to switch the ecu with an OBD1 and MAF. That's why I created the thread to clear up some confusion I was having.

I think I'm going to go with a 1j vvti for the powerband and to keep my dash from looking like a christmas tree lol

Ali SC3

iTrader: (10)

both swaps will work, you just need the right harness.