88 DX to 90 Si Help...

[drasticdezignz]

Hey,

I am not sure if I hooked everything up right, or I have extra plugs, or something is missing from my harness... but anyways.....

I have one extra plug from the stock DX harness.... which I think is supposed to be okay, but then I have this square two pronge plug on the back/bottom of the intake manifold, that looks alot like the plug on the map sensor.... so ... can anyone help me out with some info... I have some info on the DX to Si swap, and I have all charts.... but they don't address the two plugs... I can't find the square plug on my DX harness, but its on my Si harness.... so.... do I need to add in a new plug in for the one on the back of the intake, or do I leave it not connected?? please help me....!!!

 

[Captinb16]

are you talking about the dx harness and the si harness. Cause on the 88si harness you will have a square plug. ANd only a 88si harness will work. 89-91 have differnt plugs. If iam understanding you right you will need to get a 88si harness. GOOD LUCK! there hard to find. unless you use a 90-93 ls harness. Which will work but the plugs that go up to the res.box (inj) will be like 12" short. Unless you can rig somthing up. It is possiable to do though.

 

[jlicrx]

let me guess - you are using 89, 90 or 91 intake manifold on the DX - if the square plug on the Si has 2 wires, black/yellow and blue, it is for the fast idle control valve on the back of the intake manifold on the driver's side - DX doesn't have this valve - just leave it not connected - it only works at extremely low ambient air temperature when the coolant is -10 degrees C (14 degrees F) to speed up the idle for faster warm-up - you should have 3 connectors left over - the 2 injector connectors and the connector for the tandem valve (from left to right)

 

[drasticdezignz]

yeah, your right... actually, I cut two of the injectors, and used them in the setup... [thats what my instructions told me to do...] as for the one on the back.... I guess I will just leave it off.... but the tandem valve.... I am not using it...

so its not going to give me any stupid check engine light warnings because of the plug not being connected on the intake manifold?

 

[mikesphat]

naw man the ecu shouldnt trip white plug pictured gets left hanging or cut. the green and brown are the injector plugs from the dpfi.

 

[jlicrx]

Originally posted by drasticdezignz@Dec 4 2003, 09:55 PM
so its not going to give me any stupid check engine light warnings because of the plug not being connected on the intake manifold?

no, shouldn't get CEL - the 89-91 Si was the only ones with fast idle control valve - 88's didn't have it, nor did DX, HF or ZC
if you wanted to hook it up, run a wire from the blue wire at connector to ECU pin B2 and connect black/yellow wire to other black/yellow wires which connect to fuse #14