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Hey guys, I have a 1985 Iroc with the 305 TPI/700R4...I am doing a swap and had some questions....I am currently having issues with the wiring. the 85 engine harness had an extra plug to the body harness that the 91 RS does not...just wandered what it was and if I need it. second the body harness and engine harness has the two connections one with 8 pins I believe and one with 6 or something..the one with 6 on the 91 body harness doesn't the number 2 pin and the engine harness is missing the number 3 pin. and lastly has anyone installed the intellatronix cluster for their 91? how did you wire it and two where does the spend sending unit from tranny plug into? I am garbage at wiring and don't know how to read wiring diagrams...i have been staring at them for 2 weeks now haha but, thank you for all the help!!!!
The 'extra plug' on the 85 harness is called C221 & IIRC it contains the fuel injector wires.
If you really want this to work and don't want to spend big $ to make it happen,..... you've got to learn how to read schematics.
The 85 and the 91 wiring systems are NOT COMPATIBLE. This is not a simple "2 or 3 wires to splice and your done' kind of conversion. If you really want to convert your 85 interior to be a 91 interior and don't know how to read a wiring diagram be prepared to pay a professional because it's not something we can walk you though in a couple web forum posts. ECM problems, Fan problems, Lighting Problems, Fuel Pump problems, Speedometer problems, SMOG problems; get ready !
I am trying to learn the schmatics but its not an overnight process...im just trying to gain some assistance in reading them and how i would go about completing this project.
You nailed it Brian,..... All 88-92 cars have Injector wires on B & G of C207.
1985 C207
PIN Color From / To (Notes)
A Brn ALDL (pin C) / ECM (AIR control)
B* Dk Blue BU Fuse / Back Up Switch ( V8 T5 )
B* Red ALDL / Fuel Relay ( V6 - TPI )
B* Org/Blk FP FUSE / Fuel Relay ( L4 )
C* Brn/Wht ECM / CE Light ( L4- V6 - TPI )
C* Wht/Grn Light Driver / ECM ( LG4 & L69 )
D* Blk/Org FP/INJ fuse / Fuel Relay ( L69 )
D* Tan/Wht Fuel Relay / Fuel Pump ( V6 )
D* Lt Blue Fuel Relay / Fuel Pump ( TPI )
D* Tan Oil Pr Sensor / Oil Pr Gauge ( L4 )
E Wht/Blk ALDL / ECM (test)
F Pnk/Blk IGN fuse / EGR-ECM
G* Dk Blue BU Fuse / Back Up Switch ( V8 T5 )
G* Pnk/Blk Gage Fuse / MAF Relay ( V6)
G* Pnk/Blk Gage Fuse / Burn Off Relay ( TPI )
G* Pnk/Blk Gage Fuse / Air Cond Relay ( L4 )
H Tan/Blk ALDL / TCC-ECM
J* Ppl Starter / Fuel Relay ( L69 )
J* Org ALDL / ECM ( L4 - TPI )
K Brn ECM / VSS
L Tan/Wht Fuel Relay / Fuel Pump ( L4 - L69 )
M Blk/Wht VSS,P/N switch / Grd
N Org/Blk ECM / P/N switch
P Ppl Brake / TCC
R Ppl/Wht Crank Fuse / Cold Start-ECM ( V6-L4 )
Plug C221
A Pnk/Blk Inj2 Fuse / Even Fuel Injectors
B Lt Green Back Up Switch / BU Lights ( V6-T5 )
C Brn Fuel Pump-Fan Fuse / Fan Relay ( V6 - TPI )
D Pnk/Blk Inj1 Fuse / Odd Fuel Injectors
E
F Dk Blue Back Up Fuse / Back Up Switch ( V6-T5 )
1990 - 1992 C207
PIN Color From / To (Notes)
A Brown ( TBI )
B* Pnk (Red) INJ1 TBI (TBI)
B* Pnk/Blk INJ1 (V6 / TPI)
C Brn/Wht ECM / CE Light
D Grey Speed ECM to Cluster (Not with TBI)
E Wht/Blk ALDL (pin B) / ECM (test)
F Pnk/Blk ECM fuse / ECM
G* Pink/Blk (white) INJ2 TBI (TBI)
G* Pnk/Blk (INJ2 V6 TPI)
H* Tan/Blk ALDL / TCC-ECM (auto)
H* Tan/Blk ALDL / Upshift (stick)
J Org ALDL (pin E) / ECM
K Brown ECM / Buffer (Only TBI)
L Drk Blue Vats to ECM
M Org Interior Lights
N Org/Blk ECM / P/N switch
P Red Speed Sensor (Not with TBI)
R Ppl/Wht Crank Fuse / Cold Start-(only TBI)
why would my 85 have an injector plug but the 91 not have one? im baffled by this...and how would i correct this situation?
All fuel injected cars ( V6 & V8 ) from 85-88 needed a new plug to account for the fuel injector power wires than earlier ( Carbureted ) cars didn't have. Those fuel injector wires were moved to C207 in 88 where they remained for all remaining Thirdgens. On the 85 harness the small "square/white" plug is the C221 plug, The small "square/black" plug is the plug for the 1985 Specific MAF Burn Off Relay. ONLY the 1985 TPI cars have that 6 PIN "square black" plug.
Realize - at this very moment - that you while you thought you were jumping into the shallow end of the pool,.... your feet never touched the bottom after hitting the water and you're 'in way over your head'.
If you're trying to install a 90-92 Dash housing into an 85 then you should probably read this thread,.....
I’m trying to fix a wire hack job on an 86 Z28. But I have one plug on the firewall I can’t ID and having a hard time finding the fan relay. Any help would be appreciated. Thanks!
Your pictures show the HVAC harness plugs on the engine harness. The HVAC harness simply plugs into it. ( should poke thru the firewall just to the right of the heater hoses.)
The Blower High Speed Relay should be screwed to a 90 degree bracket on the engine side Blower box. Relay should be a square shaped ,...... Sounds like you might be missing a HAVC harness ??
Your pictures show the HVAC harness plugs on the engine harness. The HVAC harness simply plugs into it. ( should poke thru the firewall just to the right of the heater hoses.)
The Blower High Speed Relay should be screwed to a 90 degree bracket on the engine side Blower box. Relay should be a square shaped ,...... Sounds like you might be missing a HAVC harness ??
Did you convert to non-AC ??
car didnt come with A/C. So this is one of those “extra plugs” that’s not used for a non-A/C car. Still trying to locate the relay for the fan. A previous owner ran a manual toggle switch from inside the car for the radiator fan. I bought new block temp sensors and rewired them into the harness. Do you have a picture of the fan relay assembly and where it is located? I have a wire diagram that says it has a Red/Black wire going to the fan motor and a Red fuseable link from the relay but I don’t see either of those anywhere. Thanks!
Interesting,..... I've got to wonder why your engine harness has the wires for AC then. Pretty sure the plug shouldn't be there if it was a factory non-AC car. Non-AC only had 3 speeds and didn't need a relay, so non-AC = No High Speed Relay.
Interesting,..... I've got to wonder why your engine harness has the wires for AC then. Pretty sure the plug shouldn't be there if it was a factory non-AC car. Non-AC only had 3 speeds and didn't need a relay, so non-AC = No High Speed Relay.
What does your Heater harness look like ??
Here’s a picture. Just to clarify I’m trying to figure out the electric fan on the radiator to cool the engine.
You had asked about the fan relay and posted a pic of the HVAC connector; but it seems like yous really need cooling fan info ??
Here is where the factory cooling fan relay is mounted on the 85-86 Carb cars.....
Ok great! So which wire does the power side of the fan on the radiator connect to? Dealing with a total rats nest unfortunately. So I think I had to questions linked together...the fan relay and the plug on the firewall. Thought they might be related. As in the heavy red wire on the firewall plug could be he power line for the radiator fan.
wow! That is the darkest, thinnest red stripe on the black wire! If you hadn’t pointed it on and the location I would have sworn it was a completely black wire! Got it figured out now! That wire battle is complete! Thanks!
05-11-2018, 06:17 PM
