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Wiring loom difference between A31 A/T RB20DET and R32 M/T RB20DET?

deuceforty2
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deuceforty2 Newbie

deuceforty2

Posted
Posted

Hey guys, I had an R32 M/T RB20DET in my S13 quite a while ago, however I have replaced the chassis harness on the S13 and picked up a new motor (A31 A/T RB20DET according to the ECU) and I am having a hell of a time trying to figure out the dash wiring (specifically the black/pink wire for the fuel pump).  It seems this A31 loom is quite different at the dash connector and there is not even a black/pink wire anywhere on the engine loom (on one of the 5 dash plugs that are there), or on the ECU for that matter.  Every pinout I have seen is totally different from the actual wires on my ECU and i'm at a loss on how to wire this thing into my S13....

 

 

Any ideas?

 

In summary : A31 A/T engine loom/ecu pinouts are different than any pinouts i have seen online (specifically around pin 18 Fuel Pump Relay) 

funkymonkey Grand Master

funkymonkey

Posted
Posted

back when I had my Ceffy (auto RB20DET) I remember the wiring being a mashup of R31 GTSR and S13, and not really R32. It all made sense when I realised the Ceffy started production in 88 and the Skyline in 89.

 

We ended up hand tracing a lot of it while trying to add an alarm/immobiliser etc.

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GTSBoy Grand Master

GTSBoy

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Posted
1 hour ago, funkymonkey said:

It all made sense when I realised the Ceffy started production in 88 and the Skyline in 89.

It all makes more sense when you realise that the A chassis are closer to the chassis than they are to the R chassis. The A was just an S with an RB, basically.

funkymonkey Grand Master

funkymonkey

Posted
Posted
23 hours ago, GTSBoy said:

It all makes more sense when you realise that the A chassis are closer to the chassis than they are to the R chassis. The A was just an S with an RB, basically.

TBH if they had brought it here and badged it a Pintara in 89, I'd have bought it. It's the spiritual successor of the R31 we developed, and not the Bluebird.

WMDC35 Experienced

WMDC35

Posted
Posted

Been a long time since I've played with those but I think C33 twin cam is the same as A31, any reason you're not using the engine loom you had before? Engine side is pretty much the same except the cir clip type plugs on A31/C33 so could swap plugs or electrics to suit.

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