Cylinder Head Removal - Wiring Harness Question

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Thread: Cylinder Head Removal - Wiring Harness Question

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    Cylinder Head Removal - Wiring Harness Question

    Hey SF. My work to replace my cylinder header gasket has begun and so far no big surprises, just the breaking of some plastic pieces due to age and heat exposure. On the main wiring harness (intake side), I'm able to see how I'll be able to disconnect and set aside wiring for cylinder head removal except for a sub-harness that goes thru the intake runners. This sub-harness has a few nearby connectors and one that goes towards transmission. I think the TSRM covers these connectors to be unplugged for cylinder head removal; just saw a list but not much accompanying detail.
    My question is to the folks who have done this work before; did you disconnect all the wires and pull them thru the intake runners for removal or is there an easier workaround?
    I did search on this and didn't really see much on how to address this wiring harness.
    One option I read was to unbolt the intake runner, leave wiring harness as-is and just set them aside and out of the way for removal of cylinder head.


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    SupraForums Member plaaya69's Avatar
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    Its not too bad especially since you got the upper intake manifold off already and yes you gently pull the wires up through the spot you mentioned. Just disconnect the 2 VSV's, 2 knock sensors, single starter wire, set of grounds and transmission connectors under that manifold and carefully lay your harness over your passenger fender, with a fender cover on of course

    You will also have to remove some connectors that are near fuse box near the battery to completely remove the engine harness out of the way. Take good care of those knock sensor wires as those are a common one to break.
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    Sounds good. I was very leery about pulling all those wires thru the intake, especially the very long one going to transmission; thanks for confirming.

    And yes, I've been very patient and careful with connectors and the wires. I've already broken 3 connector clips but those couldn't be help because they're so hard and won't move to unlock connectors.

    Update: Finally got the harness out of the way; broke locking tabs on three injector connectors but surprisingly the rest of connectors came out fine. I also managed to unbolt turbo and will try to remove everything on the exhaust side today. Looking at pulling the head tomorrow or Monday since I'm waiting on a loaner engine hoist to lift the head.
    It's taking me awhile getting things done since I only have maybe 4 hours each day to work on the car . Hopefully, I won't forget too much and get things back together correctly .

    Last edited by OldBonus; 05-04-2019 at 02:49 PM.

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    One thing that helps me come reassemble time is I group the bolts together and put them in the small snack-size zip-lock bags and label each bag with a sharpie based on where they go. Then when it's time to put everything back together, I just have the find the right bolt and nut sack (hehe, I said nut sack); kind of like putting together a big Lego kit where parts are grouped together and labeled so they are easy to find when needed.

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    addicted redwind's Avatar
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    Quote Originally Posted by OldBonus View Post
    Looking at pulling the head tomorrow or Monday since I'm waiting on a loaner engine hoist to lift the head.
    I just pulled it by hand. Honestly once everything is off the head (cams/manifolds) Its really not that heavy. you will need a pry bar to break the seal though, just dont pry under the head.
    I used the exhaust and intake studs and very carefully got it to move then just pulled off by hand.
    Quote Originally Posted by vCo2v View Post
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    Quote Originally Posted by jonnymkiii View Post
    One thing that helps me come reassemble time is I group the bolts together and put them in the small snack-size zip-lock bags and label each bag with a sharpie based on where they go. Then when it's time to put everything back together, I just have the find the right bolt and nut sack (hehe, I said nut sack); kind of like putting together a big Lego kit where parts are grouped together and labeled so they are easy to find when needed.
    Yeah, pretty much had most of small parts in plastic bags with labels and also in small containers. I also took a lot of pictures during different stages of disassembly which I'm hoping to help me get thru the reassembly. (lol! you just reminded me of this from fast and furious -" yo nut sack! ….muscle beats import every time ... every time!")

    Quote Originally Posted by redwind View Post
    I just pulled it by hand. Honestly once everything is off the head (cams/manifolds) Its really not that heavy. you will need a pry bar to break the seal though, just dont pry under the head.
    I used the exhaust and intake studs and very carefully got it to move then just pulled off by hand.
    You're right, when I broke the head gasket loose, the head didn't feel that heavy.
    So, I reached over from the driver's side fender and lifted the head up and over. I didn't bother removing the cams and intake runner - the intake runner makes for a good hold when lifting.

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