Need help, trying to remove intake plenum

msvx95 · #1 05-26-2011, 07:19 PM

I have removed 4 bolts on each side of the intake (collector) or plenum..not sure the terminology. I also removed the wire harness bolt that mounts to the black bracket that holds the alternator wireway.

I'm trying to figure out what else is holding the collector down...I can wiggle it but it feels like something is still attached. Did I remove all the bolts or is there something under the collector or in the back?

P.S. the throttle body is off and out of the way.
Also I'm not removing the manifold bolts...those are lower..I just want the plenum (collector) off.

Crazy_pilot · #2 05-26-2011, 07:37 PM

There's a whole nest of vacuum and fuel lines that hold it down as well. The easier way is to remove the 14 bolts holding the injector stacks to the cylinder heads and remove everything together. You will have to disconnect the fuel rubber fuel lines from the manifold and the brake booster vacuum line from the drivers side stack, plus the two vacuum lines that go to the EGR on the passenger side rear of the manifold. Keep an eye out for electrical connectors, there's one under the manifold that holds it to the engine. Once everything's off it's simple to remove those 8 bolts again and take the manifold off the stacks.

msvx95 · #3 05-26-2011, 08:02 PM

So are you saying that in addition to the 8 bolts I removed already, I have to remove 14 more for the fuel rails and then 8 for the manifold? Do I need to remove the 8 on the manifold? I didn't purchase gaskets for those, just for the plenum.

Any chance you have a visual on the 14 bolts for fuel...and I'm hesitant to remove anything fuel related. Do I need to unplug the pump under the rear seat as well and pinch off the lines?

Crazy_pilot · #4 05-26-2011, 10:57 PM

Put the 8 bolts back in and then remove the lower 14. It might sound like more work, but it's really much simpler. The fuel hard lines are attached to both the stacks and the manifold, and there are several vacuum lines that snake through the whole mess.

Actually, svxfiles has the service manual instructions for removing the manifold in his locker. Here you go:

You can see they remove the entire manifold and fuel injector assembly as one. Yes, you have to remove fuel lines, but it's MUCH less complicated than trying to disconnect everything else. Once you have the whole thing off flip it upside down and take a look, you'll see what I mean.

msvx95 · #5 05-27-2011, 05:40 AM

Nice, ok I will look at this. Much needed info that I see is very helpful.

Ok, important question though. I already disconnected the throttlebody and a bunch of hoses, but didn't disconnect the fuel pump and start the car to relieve the fuel pressure. What should I do? Can I still disconnect the pump and crank the engine until it stalls? (The fuel lines are still connected...just vaccuum hoses and all hoses related to the throttlebody are off.
Please advise,

Thank you.

Crazy_pilot · #6 05-27-2011, 10:40 AM

Honestly if you just pull the fuel lines off not much happens. There will be some leakage, but nothing significant. Keep a rag under the lines as you disconnect them to soak up the spilled gas, and maybe wrap one around to shield any small spurts. The pressurized one is the line off the top of the fuel filter. One is a return line and the last is just a vapour line (the one with the spring clamp.)

They will be very stiff coming off, you'll probably have to twist them first to get them moving (you'll hear a crack when they break loose). Also to make putting them back on easier you can apply a SMALL amount of oil to the metal fittings.

Reading over those instructions it says to remove the alternator, drive belts and a bunch of other crap. I never had to do that for mine, but I also don't have an A/C compressor. Use your judgement on that. If it looks like everything should work with the A/C and alternator still in place I'd leave them, saves a bunch of work.

msvx95 · #7 05-27-2011, 12:21 PM

I was just going to pose that question about the alternator and compressor. I really really want to leave them there without disconnecting them. What's the point of removing those anyways. I would think the intake comes up slightly, then back so those components are out of the way.

msvx95 · #8 05-27-2011, 08:02 PM

Almost done taking it apart. A few hours into it and I still have to disconnect the fuel lines near the charcoal canister. There were more bolts to remove than I thought.
I have a lot of oil under there and I'll have to take pictures so maybe I can be advised what to replace.
So far I think the iris valve was leaking oil..is it supposed to have oil anywhere near it??

Crazy_pilot · #9 05-27-2011, 09:57 PM

The intake typically pulls oil through the PCV valve and it sits in the IRIS and leaks through the hole that the center shaft goes through. It's a common thing and I don't really know what to do to fix it aside from a new IRIS or trying to take it apart and replace the o-rings inside.

garbanzo11 · #10 05-28-2011, 04:42 PM

i had mine off not too long ago. you'll need to be careful, as there are several solenoids located on the left and right sides, under and attached to the plenum. the vacuum lines may be really brittle, and you may be better off to cut them, and replace them, rather than risk breaking off the nipples on the solenoids. if the nipples Do break, a good trick is to use a straw from a can of penetrating oil, stick one end into the broken solenoid, then slide the broken piece down the straw, and superglue it together.....just remove the straw before it sets up. my oil issue was from the large valve, round and about 4" in diameter. i tried to replace the o-ring, but it didn't work, so i replace the valve...($450) ouch! anyway, hope this helps. good luck.