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How to Replace Intake Manifold 99 Pontiac Grand Am

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How to Replace Intake Manifold 99 Pontiac Grand Am

Created on: 2013-09-30

If the intake manifold gasket is leaking or broken, this video will show the steps for replacing it

  1. step 1 :Removing the Spark Plug Wires
    • Unplug each of the spark plug wires - remember their order
    • Remove the spark plug wires from their clip
    • Remove the two vacuum hoses
    • Remove the 10mm bolts from the throttle body bracket
  2. step 2 :Removing the Air Intake
    • Loosen the air intake hose clamps with a flat blade screwdriver
    • Remove the air intake hose from the intake manifold
    • Disconnect the vacuum hose on the air intake hose
    • Disconnect the EGR harness
    • Remove the air intake hose from the air box
  3. step 3 :Disconnecting the Intake Manifold
    • Remove the two 13mm bolts from the throttle body
    • Remove the 10mm bolts from the top of the coil pack
    • Remove the 13mm bolts from the bottom of the coil pack
    • Slide back the hose clamp with a pair of pliers on the back of the intake manifold
    • Disconnect the hose
    • Remove the two 7mm bolts from the back of the MAP sensor
    • Disconnect the MAP sensor harness
    • Remove the sensor
    • Remove the hose with a flat blade screwdriver
    • Remove the two 10mm bolts from the EGR Valve
  4. step 4 :Loosening the Upper Intake Plenum
    • Remove the 10mm bolts from the upper intake plenum
    • Remove the 13mm nut from the upper intake plenum
    • Remove the 10mm bolt below the right side of the intake manifold
  5. step 5 :Disconnecting the Coolant Hoses
    • Remove the cap on the radiator overflow bottle
    • Slide a drip pan underneath the drain plug
    • Remove the drain plug and drain the coolant
    • Pry off the coolant hoses
    • Remove the hoses from the top of the manifold
    • Replace and tighten the drain plug
  6. step 6 :Removing the Upper Intake Manifold Plenum
    • Lift the upper intake plenum up and aside
    • Remove the 13mm nut from the throttle body
    • Remove the throttle body
    • Remove the upper intake plenum
  7. step 7 :Installing the Upper Intake Manifold Plenum
    • Insert the 13mm nut to the throttle body and intake plenum
    • Insert the upper intake manifold plenum into place
    • Insert the 10mm bolts from the upper intake plenum
    • Insert the 13mm nut from the upper intake plenum
    • Torque the 10mm bolts to 18 foot-pounds
  8. step 8 :Installing the MAP Sensor and Throttle Body
    • Insert the two 7mm bolts from the back of the MAP sensor bracket
    • Connect the MAP sensor to the lead
    • Connect the sensor to the intake manifold
    • Tighten the 7mm bolts to the MAP sensor
    • Insert the 10mm bolts from the top of the coil pack
    • Insert the 13mm bolts from the bottom of the coil pack
    • Insert the hose and hose clamp on the back of the intake manifold
    • Insert the vacuum hoses to the intake manifold
    • Remove the rubber plug on the old manifold plenum to the new one
    • Tighten the two 13mm bolts to the throttle body
    • Tighten the 10mm bolts to the throttle body bracket
  9. step 9 :Installing the EGR Valve
    • Slide the hoses onto the coolant line
    • Tighten the hoses with the clamp and pliers
    • Place the gasket below the EGR
    • Insert the EGR and tighten the 10mm bolts
  10. step 10 :Installing the Air Intake
    • Loosen the air box with a Phillips screwdriver
    • Push the air intake hose into the throttle body
    • Tighten the Phillips screws on the air box
    • Tighten the air intake hose clamps with a flat blade screwdriver
    • Connect the vacuum hose on the air intake hose
    • Connect the EGR wiring harness
  11. step 11 :Installing the Spark Plug Wires
    • Clip in the spark plug wires clip
    • Plug each of the spark plug wires by number
  12. step 12 :Refilling the Coolant
    • Insert a funnel into the coolant bottle
    • Refill the coolant as needed

Tools needed for replacement

  • General Tools

    Funnel

    Drain Pan

  • Pliers, Cutters & misc Wrenches

    Needle nose pliers

  • Ratchets & Related

    Socket Extensions

    Torque Wrench

    Ratchet

  • Screwdrivers & Related

    Flat Blade Screwdriver

    Phillips Head Screwdriver

  • Sockets - Metric

    13mm Socket

    10mm Socket

Installation Video
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Brought to you by 1AAuto.com, your source for quality replacement parts and the best service on the Internet.

Hi, I'm Mike from 1A Auto. I hope this how-to video helps you out, and next time you need parts for your vehicle, think of 1AAuto.com. Thanks.

In this video, we're going to show you how to replace the upper intake manifold on a 3.4-liter GM V6. The car we're working on here is a 1999 Pontiac Grand Am, but they use the 3.4-liter in a bunch of different cars. You'll need 10mm and 13mm sockets with a ratchet, a flat blade screwdriver, a Phillips screwdriver, pliers, a drip pan, and a funnel with the screen or a filter.

Take the plug wires off the front of the engine from the passenger side back to the driver side. It's two, four, and six. You have to make sure that you put the wires back on in the correct order. Our original wires are marked two, four, and six. You'll want to mark yours two, four, and six, just to make sure you plug them back in. Then pull off, pull, and twist at the same time and they'll come off.

Now you just want to disconnect the spark plug wire. There's a clip up there, you just want to pull that off. Then you just want to remove that hose from the top and that hose as well. On this clip right here, you'll see there's a 10mm bolt. Just go ahead and remove that. Now, what you want to do is loosen up the clamp on the air intake hose. Using a flat blade screwdriver, just loosen up the bolts on those two clamps. With those loosened up, you can pull the hose off. You just want to pull that back in a way.

Now disconnect the hose connected to the top of that and the harness on the side; pull it free and away. Now, as you can see right here, there's two 13mm bolts: one up the top corner and one diagonally across from it. You just want to go ahead and remove those.

Next, what you want to do is remove the bolts that secure the coil pack. There's actually different size bolts. The top two are 10mm and the bottom two on the back are 13mm. You just want to go ahead and remove those. Now, using a pair of pliers, you just want to grip that clip and slide it back on the hose. Then you just want to use a flat blade screwdriver to pry that hose off.

Now right here, there are two 7mm bolts. You just want to go ahead and remove those. Now with those bolts removed, you can just disconnect the harness on the bottom and pull that up and out. Then, using a flat blade screwdriver, just pry that hose off.

Now, on either side of the EGR, you can see that there are two 10mm bolts. You just want to go ahead to remove those. Now what you want to do is remove this upper intake plenum. What you're going to need is a 10mm socket to remove the 10mm bolts, and then there's one 13mm nut right there. You just want to go ahead and remove all those.

Now you just want to remove this 10mm bolt right here. Now you just want to remove the cap on your radiator overflow bottle. Then you want to take a drip pan and slide it underneath the engine. Right underneath these hoses right here. You want to take some pliers, push those clamps, slide them back on the hose.

Then we're going to take a flat blade screwdriver and we're just going to pry that hose back and off. It's important to disconnect these hoses. You're going to see a lot of coolant come out that's why the drip pan is under there. We actually leave the screwdriver in there to help drain all this coolant. However, there is an easier way to drain this coolant. In our case, this is how we had to do it, and you can do it this way. But what you should do to drain your coolant quicker as you can see there's actually a bolt right there. You just want to loosen that up and drain the coolant that way. Ours is actually broken, so we didn't have a choice. Once the coolant is pretty much drained out, you still want to make sure those hoses are pried off. Then you can just pull that hose free and that hose free.

Next thing you want to do is just lift this up. We can just set that aside. Now what you want to do is remove this 13mm nut from the throttle body. The throttle body should come right off, and your upper intake plenum you can now pull away.

Here is the old one on the right; the new one from 1A Auto on the left. It's the exact replacement.

You just want to put your new upper intake plenum back into the motor. Just reattach that throttle body to put that bolt back in there and tighten that up. Take your upper intake plenum. You want to just line it up. Make sure this harness goes up through that hole in the back on your right there, and then just put that plenum into place. You want to just replace all the bolts that go along this.

Make sure that if there's a bracket that goes in that spot, you put the bolt down through the bracket like right here. With this bracket, you want to make sure that the harness goes underneath it. You want to just take this, plug it in right next to that harness, and then plug the other end up here. Then take this, plug that lead into it and set that down into that bracket. You want to just tighten those bolts.

You want to just replace your coil pack bolts to secure the coil pack back into place. Just tighten those up real quick. You want to just put that hose back into place. Take the clamp, using pliers slide it forward, and lock it into place. You want to push this hose back into place. Same thing with this one you want to replace the two bolts back down underneath the coil pack. You want to just reach down there using a flashlight to see where the holes are and put those back. Do it by hand first and then tighten them up.

Then you want to bolt your throttle body back into place. Then you want to replace that nut on the bottom corner of the throttle body. Just replace the bolts up above the throttle body and tighten them. Take this hose here, push it back, and then slide it down into place. Then you want to take your pair of pliers, push that clamp together, and slide that forward.

Then you want to take this hose. You can see, using a flat blade screwdriver, he's just positioning the hose onto that into place there, and then it just slides into place. Again, take pliers, push the clamp forward, replace that bolt, and tighten it.

Now, before putting your EGR on, put the new gasket from that gasket pack into place and then line up you EGR. Put that into place and replace the bolt on either side. Now, what you want to do is put the air intake hose back in, so you want to use a Phillips screwdriver to loosen up those bolts. Pull the intake cover back, put the hose into place, and then slide that cover forward until you can snap it down into place. You just want to tighten up those Phillips screws, get a flat blade screwdriver, and tighten up the bolts on the clamps.

Just take this connector and plug it back in. Then you want to take these hoses and put them into this clip. Right down here, you can see there's a hole, and over here there's another hole. You want to take this, fit that down in behind and into the hole there. Wrap it around and plug it into the hole at the top of that air intake hose.

Then you want to take your EGR connector and plug that back in. Now you can plug in your spark plug wires. You just want to clip that clip back on right there and then push those wires down into place. Now, using a funnel with a screen or a filter in it, you want to just pour that coolant that came out into the drip pan back into your reservoir bottle.

We hope this video helps you out. Brought to you by www.1AAuto.com, your source for quality replacement parts and the best service on the Internet. Please feel free to call us toll-free, 888-844-3393. We're the company that's here for you on the Internet and in person.

Tools needed for replacement:

    General Tools

  • Funnel
  • Drain Pan

  • Pliers, Cutters & misc Wrenches

  • Needle nose pliers

  • Ratchets & Related

  • Socket Extensions
  • Torque Wrench
  • Ratchet

  • Screwdrivers & Related

  • Flat Blade Screwdriver
  • Phillips Head Screwdriver

  • Sockets - Metric

  • 13mm Socket
  • 10mm Socket

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1999 - 1999  Pontiac  Grand Am
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1996 - 1999  Oldsmobile  Silhouette
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