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Posted: **Thu May 24, 2012 8:12 pm**

Okay, so I've done my best to do a search on this board and many others, but I couldn't find a really comprehensive writeup on the engine wiring. If one exists or someone has pictures with labels from their own rebuild I would be greatly indebted.

So I have an idea of where the fuel injector harnesses go, luckily they are labeled by number to the respective cylinders (please correct me if I am wrong). I realize a lot of the harnesses should just fit due to proximity, but I just want to be extra sure before I start trying to force prongs where they shouldn't go. Like I've mentioned before, nothing was labeled when this engine was pulled apart (which is a mistake I would never make again)

Here is a full view of the wiring harness, with my arbitrary and poorly designed divisions :-p

Closeup of the middle

Part A, which extends from the PCM I believe. I've kind of separated each specific plug by letter and number and these are the ones I am not entirely sure of.

Part B

Zoom out of C, with random plug at bottom I forgot to label, we can call it U1

Part C

Part D

Part E

Part F, Again, you can see where U1 bridges C and F

Part G, if you look closely, fuel injector 2 extends on the left from the two G1 and G2, and fuel inject 4 extends from the same root as the single G3

Part H, I am guessing the big one goes to the back right section close to the firewall, but not sure about that vacuum looking piece (H1)

This I am calling part X, these guys are just separate from the big loom altogether.

Anyway, if anyone happens to have notes, pictures, or even remembers where all of these go I would be forever gracious!!

Posted: **Fri May 25, 2012 2:36 am**

If that harness is going back into a car designed for that harness with an engine designed for that harness then it is all very simple. Basically lay the harness out over the engine, and start connecting it. As you said, all of the plugs will be very easy to tell where they go by proximity, as well as what they fit into. These harnesses are fairly simple when you really get into them, there really isn't two plugs that can reach the same place that look the same that can be plugged in wrong, pretty much everything can only go into the right spot based on where it is in the harness and what sensors are available to that area.

Posted: **Fri May 25, 2012 12:56 pm**

crash93ssei wrote:If that harness is going back into a car designed for that harness with an engine designed for that harness then it is all very simple. Basically lay the harness out over the engine, and start connecting it. As you said, all of the plugs will be very easy to tell where they go by proximity, as well as what they fit into. These harnesses are fairly simple when you really get into them, there really isn't two plugs that can reach the same place that look the same that can be plugged in wrong, pretty much everything can only go into the right spot based on where it is in the harness and what sensors are available to that area.

^ x2

Posted: **Fri May 25, 2012 1:57 pm**

In case someone needs it

BillBoost37 wrote:Based on the harness (you didn't say what it was for) I can tell this is a 96 H body SC car.

Ready..this is all from from my head and you can trust it.
A Pcm connectors (match blue to the blue label on pcm and clear to clear)
A1. Trans connector for a 4T60E
A2. Power steering connection (magnasteer)
A3. Park neutral safety switch (on top of trans)

B1. Front O2 sensor (96 was a flat connector like this, 97 would have been a square)
B2. Map sensor (rear of engine)
B3. Looks like a 10 wire, but is in the right place to be EGR. If it's 5 wires..it's EGR
B4. Vacuum line (connects to center port on top of SC, is the other end to H1)

C1. ICM/Crank/Cam harness (other side typically stays on the motor. Connects right by FPR)
C2. Coolant temp sensor (under top rad hose connection at engine)
C3. BCS or boost control soleniod (next to #5 injector)
C4. IAC
C5. Either MAF or TPS connector, oddly there should be two of these with a purple seal on them. One for the maf, one for tps. You appear to be missing a connector in the C's.

D1. Oil pressure sensor (back passenger side of motor above oil filter)
D2. Rear knock sensor (Connects to X4 to give you a pigtail for installation, makes connection to rear knock sensor much easier)
D3. Not 100% on this one, I believe the power steering pump in that year had a connection and this should be it.
D4. VSS akd Vehicle Speed Sensor (connection on diff cover of transmission by passenger inner cv boot.)

E1. Rear O2 sensor (this wire runs into a metal shield along the exhaust tunnel under the car.

F1. Front knock sensor (located between AC compressor and starter)
F2. Oil level sensor (front of oil pan by ac/starter)
F3. AC high pressure switch (also by AC compressor)
F4. Starter soleniod (small bolt on starter soleniod)
You should have one more F connector for the AC compressor.

G1. Either the evap purge valve or the evap switch (location behind alternator)
G2. Alternator
G3. Same as G1 (if G1 is valve, this is switch)

H. C100 main electrical harness connection that connects near passenger strut tower on firewall.
H1. Other end of B4, it connects to the vac hose you'll find near H

X1. This is the evap purge valve.
You should also have a rectangular black box that would hook to the empty port (not the L hose, the other open port) The rectangle is the evap purge switch.
X2. On the front driverside end of the head, there should be a metal tube bolted up. This hose connects there. if you don't have the tube, run this hose to the evap canister labeled evap.
X3. Rear knock sensor connection end of the rear knock sensor pigtail. The pigtail is this small harness piece you have labeled X3 and X4
X4. End of harness the connects to D2. When lowering in the motor w/o the harness on it, this small pigtail makes it easy to connect to the rear knock sensor because it is hidden up between the engine and trans.

In summation, you are missing two connectors. One is either your TPS or MAF sensor (depending on how it's keyed) and the other is the AC compressor connector (two pin) that controls the compressor on/off.

Yep, I may have done this too many times.

Posted: **Sun Jun 24, 2012 12:56 am**

In another thread, I mention that I am switching out the 4t60E HD that came with my car to a 65E HD. To prepare for this I pulled a 1998 SE N/A wiring harness set and PCM that had the big round green 65E plug.

One thing I noticed on the L36 harness compared to the L67 one that came with my car was that it also had a plug for something on the left of the upper intake manifold. I've posted a picture below (bottom left):

Is this going to cause a problem? Can I still use this wiring harness on the L67?

Posted: **Sun Jun 24, 2012 1:20 pm**

That's the MAP sensor plug, which is in a different location on the L36 than the L67, and is a different design too. You can utilize it, just cut the harness off of the L67 and solder/shrink that to the L36 harness. Or just take the L36 map harness out altogether.

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Where do these go Part II (L67 Engine Wiring harnesses)

Where do these go Part II (L67 Engine Wiring harnesses)

Re: Where do these go Part II (L67 Engine Wiring harnesses)

Re: Where do these go Part II (L67 Engine Wiring harnesses)

Re: Where do these go Part II (L67 Engine Wiring harnesses)

Re: Where do these go Part II (L67 Engine Wiring harnesses)

Re: Where do these go Part II (L67 Engine Wiring harnesses)