How do I get the intake manifold off?

[Atreus21]

What bolts hold it down? So far I only see one near the throttle body.

This is 1998 3.8 camaro btw.

Do I have to remove the throttle body?

If I get the bolts off, will I need a whole lot of force just to move it?

[T-Mill]

Re: How do I get the intake manifold off?

are you talking about the upper intake? if so there are bolts (I can't remember how many) all around the intake bolting it to the lower intake manifold as well as a few longer ones near the throttle body

[Atreus21]

Re: How do I get the intake manifold off?

are you talking about the upper intake? if so there are bolts (I can't remember how many) all around the intake bolting it to the lower intake manifold as well as a few longer ones near the throttle body

Thankfully only the upper.

I've been looking around autozone's site. They're useful in that they have those repair manuals online. It sez this:

1.Disconnect the negative battery cable. Relieve the fuel system pressure.

How do I relieve fuel pressure?

2.Drain the coolant into a suitable container.
3.Remove the serpentine drive belt.
4.If necessary, remove the transmission fluid level indicator.

Where is this level indicator?

5.Remove the alternator and the serpentine drive belt tensioner.

By which I assume they mean the tensioner pulley.

6.Remove the Manifold Absolute Pressure (MAP) sensor and vacuum source from the upper intake manifold.

What and where is the MAP sensor?

7.Remove the evaporative emission canister purge solenoid valve.
8.Remove the fuel pressure regulator and canister purge harness.
9.Remove the Idle Air Control (IAC) valve from the upper intake manifold.

What are all these things?

10.Disconnect the fuel lines from the fuel rail.
11.Remove the accelerator control cable bracket bolts/screws, bracket and accelerator control cables from the throttle body.
12.Remove the ignition coil pack/control module assembly.

No problem. I know where these things are.

13.Disconnect the brake booster hose from the upper manifold.
14.Remove the alternator brace from the upper manifold.
15.Detach the electrical connectors from the idle air control, throttle position, mass airflow and intake air temperature sensors.
16.Unfasten the wiring harness from the rosebud clips at the fuel rail.
17.Remove the air cleaner, outlet rear duct and resonator duct.
18.If necessary, remove the throttle body from the upper intake manifold.
19.Remove the EGR valve outlet pipe.

Excluding the EGR valve outlet pipe, I think I can figure out the rest.

The thermostat must be removed to get to the "hidden" bolt located under the housing. This bolt retains the upper and lower manifolds.

20.Remove the thermostat and thermostat housing.
21.Detach the electrical connectors from the fuel injectors. Clean the fuel injector bores using compressed air.
22.Unfasten the fuel rail nuts, then remove the fuel rail.
23.Unfasten the upper intake manifold retaining bolts/screws, then remove the upper manifold and gasket. Discard the gasket and clean the mating surfaces and bolt threads.

I can figure out most of this. My foremost problem is the very first step: how to depressurize the fuel system. Do I need a vacuum pump?

[cam98aro]

Re: How do I get the intake manifold off?

Well, I need to replace the manifold gasket.

I've been looking around autozone's site. They're useful in that they have those repair manuals online. It sez this:


How do I relieve fuel pressure?

find the schrader valve and press it with a rag covering it so gas doesnt squirt anywhere, or leave your car sitting for a few hours and there should be little to no pressure


Where is this level indicator?

it is a dipstick with a red handle, it should be near the cowl plastic cover on i think the drivers side of the engine


By which I assume they mean the tensioner pulley.

correct



What and where is the MAP sensor?

im not really sure on this one

What are all these things?


No problem. I know where these things are.



Excluding the EGR valve outlet pipe, I think I can figure out the rest.



I can figure out most of this. My foremost problem is the very first step: how to depressurize the fuel system. Do I need a vacuum pump?

my answers are in bold.

[Atreus21]

Re: How do I get the intake manifold off?

my answers are in bold.

When you say leave the car sitting while the shrader valve is depressed, do you mean leave it running?

If so my car will overheat. No coolant.

Where is this valve? On the fuel rail?

Also, I'm an idiot for not knowing the transmission fluid level indicator was the freaking dipstick.

[Blizzard242]

Re: How do I get the intake manifold off?

For the fuel pressure, you can pull the pump fuse and start it and let it die. Then I check my schrader valve for any remaining pressure. You may get some pressure still and it will come out of that valve so be ready with a rag or something to catch any excess. You don't want the car running if you're pushing the schrader valve in.

Or like cam98aro said, if you just let the car sit for a long time not running the pressure will die off on its on. It's always good the check the schrader valve afterwards though to make sure.

[Atreus21]

Re: How do I get the intake manifold off?

For the fuel pressure, you can pull the pump fuse and start it and let it die. Then I check my schrader valve for any remaining pressure. You may get some pressure still and it will come out of that valve so be ready with a rag or something to catch any excess. You don't want the car running if you're pushing the schrader valve in.

Or like cam98aro said, if you just let the car sit for a long time not running the pressure will die off on its on. It's always good the check the schrader valve afterwards though to make sure.

I've gotten to step 10, having skipped steps 7-9 because I think I'll discover them when I have to.

Where are the flair nuts connecting the fuel lines to the fuel rail?

[timthescarred]

Re: How do I get the intake manifold off?

Guess you got the MAP then.

The fuel lines connect using a "quick release" connector about one inch before they go into the fuel rail. You need a special tool to release them but you can get it at most auto-parts stores for around $2-3 each. There are two sizes you need but i cant remember them off hand, they are based on the diameter of the hoses. Ask for "Fuel line disconnect tools" and the guys will help.

[Atreus21]

Re: How do I get the intake manifold off?

I found the tool for the quick release connector on the fuel line, but it's anything but a quick release. Supposedly I'm supposed to clamp down on the line with the tool and push against the fitting to release the line. I'm pushing on it so hard the tool bends and I'm worried I'm going to damage the line.

How the hell does this thing work?

[T-Mill]

Re: How do I get the intake manifold off?

you don't have to squeeze too hard, just enough to get it inside that fitting, don't just push straight in if it won't go... work it back and forth and try to rotate it in... the metal fitting may have corroded a bit and seized itself, but if you work it in, move it around you'll feel it eventually "slide" in and then you can just pull the fitting apart

[Atreus21]

Re: How do I get the intake manifold off?

you don't have to squeeze too hard, just enough to get it inside that fitting, don't just push straight in if it won't go... work it back and forth and try to rotate it in... the metal fitting may have corroded a bit and seized itself, but if you work it in, move it around you'll feel it eventually "slide" in and then you can just pull the fitting apart

Rotate the tool in, you mean?

[T-Mill]

Re: How do I get the intake manifold off?

yea... rotate, shimmy, wiggle, tap, whatever... lol

also try tapping on the fittings with a wrench before inserting the release tool to knock loose any corrosion that may have built up...

I think I actually may have inserted the tool and then gently tapped it in with a hammer on one of my cars...

[Bandit127]

Re: How do I get the intake manifold off?

Ahh, the amazing "quick" disconnects. Be happy it isnt a Ford engineered disconnect, those truly suck.

What I do is:
A.Spray with WD-40 or PB Blaster (penetrating oil)
B.Push and pull the lines into each other and try to spin the inner line a little bit to break it free inside.
C. WHILE PUSHING THE LINES TOGETHER insert the disconnect tool, wiggle, twist, tap, whatever to get it to move in, THEN PULL APART.

I found that trying to push the tool in while it has pressure trying to pull apart usually just binds up the little tabs that get pushed out by the tool, so holding pressure to pull the lines together allows the tool to slip in and push the tabs out much easier.

When I redo my fuel lines, I'm going to put 17mm and a 19mm nut style connection (like the fuel filter) because I hate quick disconnects.

[Atreus21]

Re: How do I get the intake manifold off?

Ahh, the amazing "quick" disconnects. Be happy it isnt a Ford engineered disconnect, those truly suck.

What I do is:
A.Spray with WD-40 or PB Blaster (penetrating oil)
B.Push and pull the lines into each other and try to spin the inner line a little bit to break it free inside.
C. WHILE PUSHING THE LINES TOGETHER insert the disconnect tool, wiggle, twist, tap, whatever to get it to move in, THEN PULL APART.

I found that trying to push the tool in while it has pressure trying to pull apart usually just binds up the little tabs that get pushed out by the tool, so holding pressure to pull the lines together allows the tool to slip in and push the tabs out much easier.

When I redo my fuel lines, I'm going to put 17mm and a 19mm nut style connection (like the fuel filter) because I hate quick disconnects.

Finally got 'em off.

Frankly, my biggest concern now is not fixing the problem, but being unable to put this whole mess back together. The accelerator throttle had to come off the throttle body, so that'll be fun.

[Bandit127]

Re: How do I get the intake manifold off?

Intake manifold? Well that's very very simple actually. Try changing head gaskets on a Ford F-350 6.0L Turbo Diesel. That job requires removing the cab off of the frame entirely. You get to the point of reassembly and think "Ohhhhh ****." And torquing the ARP head studs to 287lb's three times.

You'll be fine if you take your time! :)