348 Intake removal and left wiring harness removal DIY

I recently removed my intake and left wiring harness in order to attempt to sort out a couple of wiring bugs, and was pleasantly suprised when Ernie, who doesn't know me from Adam, called and walked me through it over the phone. I have never had that happen on any of the other car forums I used to frequent, and thought the least I could do would be to do a write up, so if anyone else ever needs to, it will be here. It's really pretty easy, and much more intimidating to look at than to do, as this was the first kinda big thing I had done. So here goes...excuse the lack of technical terms for some parts. I had to "dumb it down" for me, and figure this might help others as well...

Remove the airbox, MAF, and connecting tubes. Pull the big air tubes on either side.

There are 4 nuts holding the airbox to the frame, and 4 rubber hoses, 2 per side.
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PARTIALLY Remove the Intake Air Controls (I think that's what they are called)
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Pull the fuel rail electrics. There is a metal push bar type release on top of each of the injectors, 4 per side. I pried up slightly as I was pushing each one in, just enough to get it to separate from the injector top.
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Unscrew counterclockwise the two big electrical plugs at the back of the motor (back of the car)
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remove the two allen head bolts per side for the fuel rail. Rock the injectors out carefully, and set off to the side a bit.
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remove the vacuum lines going to the "white things" in the picture. They snake under the intake to what I call vacuum solenoids. I left them hooked up to the vacuum solenoids as the solenoids have several places to hook up hoses to, and I didn't want to end up hooking back up to the wrong one.
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unattach the throttle cable. Just roll the throttle down by hand and move the cable out of the way, no tools required.
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Pull the vacuum hoses from the intake to the Fuel Pressure Regulator and the intake to the Charcoal canisters, at the front of the intake. One pops off and the other requires a very small screwdriver to get to the worm drive. Also pull the vacuum hose off the back of the intake.
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Remove the IACs completely. There is a 10mm bolt underneath the intake that holds a clamp.
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Remove the two grounds per side, that are bolted to the valve covers.
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Remove the 20 bolts that hold the intake on, 10 per side. The rearmost (back of the car) inner bolts on both sides hold the vacuum solenoids on referenced earlier, and a wire loom holder, and the front innermost bolts hold a wire loom holder and the fuel pressure regulators on.

After getting all those bolts off, there is one vacuum line underneat the intake that you have to remove before you can pull the intake. I didn't get a picture of it, but you will see it. You also have to feed the injector wiring through the intake while it's coming off. I lifted up the intake and disconnected the vacuum hose, and twisted it a little bit to keep from setting it back down onto everything, then started feeding the wires through it while I was lifting it off. It was a little tricky, but not too bad. You can see in the picture the part of the harness that has to be fed through the intake. And you are done. I actually pulled the fuel injection wiring completely off just to give myself a little more room, and there are blue connectors that hold it to the top of the motor (sorry no pictures)
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I didn't take many pictures of removing the left wiring harness, with a couple exceptions. There is a harness holder bolted to the top of the plastic housing at the front of the motor, that I could not get to. I ended up having to drain the coolant, and pull one of the hoses to get to it. Also, there is a holder at the back of the motor that is easy to get to. At this point, everything is freed up from the back of the car. Remove the ECU cover, remove the two bolts holding the ECU to the car, and use the lever on the big plug to get the harness free of the ECU. I figured out that I had to slide the plug through the hole and then sideways to get it to clear the motor. After that, it came down to disconnecting everything, labeling, and seeing what went where.
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On the O2 sensor connectors, I couldn't snap them out of their holder, so I ended up having to bend the holders a bit to get the wiring harness portion out. There is also a circular connector right behind them that connects the right and left side wiring harness together. Disconnect.
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Making sure to label everything before pulling it out, I ended up with grouped connections for:
Speed Sensor
Left IAC
Charcoal canister top
Charcoal canister bottom
_______________________
two grounds
_______________________
male circle plug
_______________________
MAF
TPS
_______________________
vacuum soleniod control
_______________________
O2 connector
O2 connector
connector to other wiring harness
_______________________
coil
rectifier?
exhaust ECU


I'd like to say installation is the reverse of removal, but as mine is still out waiting on new harness connectors, we'll have to wait and see.


As a PS, as soon as the intake is off, vacuum out the holes that lead to the valves, and then shove some shop towels down in the holes to keep from anything getting in there. I'm also going to vacuum again when I remove the shop towels, just to be safe.
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