How to Replace Intake Manifold 1999-2007 Chevy Silverado

Let's get this cover off of here using our 8-millimeter socket. What we need to do now is remove this right here. To do that, you would loosen this clamp right there using either a flat-head screwdriver or an 8-millimeter. You can come over here, do the same thing, loosen that right up. You don't necessarily need to take them off completely. And then if you were to look right under here, you're going to see where these hoses should be kind of mounted in and held securely. You would just pop that free. Let's start taking this off.

Okay. One's already free. Grab onto this, slide it off. Slide that up and out of here. Now we're going to get this out of the way. We're going to remove these three 10-millimeter bolts. Let's grab this right back here. Grab that tab, lift it up, and then you should be able to slide it off. Come right over here. Same thing with that tab. Slide this off. Set it aside. I'm just going to get this right off of here. Just grab my small pocket screwdriver right in between here, a little twist, slide that out of there. Now, let's remove this 10-millimeter nut. Grab this, lift it up, gives us a little bit of slack. Now, we're going to disconnect the wiring for our throttle body assembly. Just come right along here, right in between this area, and give it a little twist. What we want to do is try to push this gray piece out. That's what's locking this in. Press right here. Draw that off. Get this hose off of here. Sometimes you can wiggle them around. You might have to twist it. I'm going to try to press a little bit with my screwdriver. Obviously, I want to be careful not to damage the hose. Get that off of there.

Let's continue on to this area right here. You're going to notice this is a little cap. Go ahead and take that off of there. Behind here, you're going to see a Schrader valve. It's almost like a little piton that's going to be sticking out in the center. What we're going to want to do is relieve the fuel pressure that's going to be inside the system. To do that, we're going to press on that center piece. You just want to be careful because it's going to be under pressure. You need to have gloves, eye protection, and it's probably a great idea to have a rag around to try to catch the majority of any fluid that might come out. Okay. So, nothing came out of there. That's great. That means that there wasn't any fuel pressure waiting in the system for me, but you definitely want to make sure that you do that anyways. Now, I'm just gonna take that cap, put it right back on there because I don't want to lose it. Up along the top of the intake, you're going to see this rubber hose that leads down to a plastic line. Let's go ahead and get that off of there. Give it a little wiggle if you need to, try to get underneath, just try to break it free.

We need to get this lock off of the fuel line where it connects onto the fuel rail. To do that, try to reach my hand in. We need to come through with our small pocket screwdriver, get underneath right here, lift this up. Once you do that, you can slide it forward, set this aside. To get the hose or the fuel line off of the rest of the fuel rail here, we're going to use this tool. I'm going to use the 3/8 side, which is the bigger side. I'm going to put it around the line and then it should go through and it's going to press up against the teeth that you can see inside. I'm going to press this in and just kind of twist it so it works its way along the teeth. If it looks as though yours is very rusted up, you probably want to put some penetrant in there. Now, I'm going to grab that hose, try to give it a little push at the same time as I do this. All right. I just felt the tool go in quite a bit. At this point, I should be able to draw this off. There we are. A little bit of fuel coming out. That's okay.

Now it's going to be time to get the fuel injector wiring harness off of here. If you were to look at it, you're going to see a big old plastic piece that's going to look kind of confusing. Why is it like that? Well, if you just take your small pocket screwdriver and press right in this little piece, you can grab onto this lip where my fingers are and draw this up. It's a lock. Okay. Pull that right up. Now, we're gonna go ahead and press on this tab again, give this a little wiggle, and it should want to separate. We're going to do the same to all the fuel injectors. Okay. So, I got the four off over on the passenger side there. Now I made my way over to the driver side. I'm going to remove the four that are on this side as well. This side might be a little bit harder to get to, but you can do it. Now we're going to get the wiring off for this purge valve here. There's a little clippy-do. You can grab onto that. Now we're going to get this hose off of here. If you were to take your small pocket screwdriver and press right here, you should be able to twist and lift. That comes right out.

Now, we're going to remove our throttle body assembly. You're going to find that there's three mounting nuts. One on top, one on the bottom driver side, and then one on the bottom passenger side as well. Remove all three. It looks like it actually pulled out the whole stud for us. It's not necessarily something to worry about, I'll show you how to put it back in. I'm just gonna see if I can work this off of here. Here we are. We'll just set that aside. Next, we're going to remove the hose that comes over to here. This just goes right to the backside of the intake. I find that this side's easier to get off. Remove that clamp. Grab your hose, give it a little twist to break it free, and then draw it right off. Let's just take a nice rag, we're going to cover the hole for the intake. The next step that we want to do is grab compressed air with a blowgun, and we're going to blow out the dirt that's in between where the intake connects onto the engine.

Next, we're going to remove the 10 8-millimeter bolts that hold the intake to the engine. You're going to notice there's five on the passenger side and then there'll be five more over on the driver side. I'm just gonna grab onto this, try to give it a little wiggle. Try to lift it up. If you feel as though it's sticking in the middle, well, check those bolts, see if they're up all the way. Okay. So, it's lifting up now. Just wiggle it around. Take a double-check around, make sure that there isn't anything that you might've happened to miss. You don't want to have any hoses or wiring connected to this in any way, anything that might pose an issue. Something to remember is as we're starting to lift this up and draw it out, this piece right here has to come through and under this area right here. So, as we come up, it might want to get caught. This is the area it's going to be stuck. Just go ahead and pull it right through there. Okay. There it is, friends.

Now, with that intake out of the way, we have a clear view of a big old mess. Any of this stuff that looks like that could be a contaminant that's going to make its way down into the engine. We obviously don't want that to happen. I'm going to grab a vacuum cleaner, you can use whatever you have. Clean this out the best you can. And then, of course, you need to take a peek inside of each of these ports to make sure there's no debris in there. Clean those out as well. Now it's going to be time to clean down the engine where the gaskets are going to ride. They're going to be along each one of these ports. Before you go ahead and scrape them down though, take a rag, fold it up, put it inside the port so it'll catch any of the debris that might fall inside. Take a nice flat razor blade, and I always just try to scrape away from the hole. Okay. So this one looks great. Go ahead and grab onto that rag. I always try to drag it along the engine so I can pull out any of the debris that might've tried getting inside. Continue wiping it down. Now, do the same to all.

Let's take the NOx sensor wire. I'm just going to go straight towards the back of the engine, around this bracket right here, and then up and over and leave it right there. You want to make sure that it's not anywhere near any of these ports because obviously we don't want to put a kink on this and we also don't want to make an issue for the gasket. So, now we're going to start transferring things over from our original intake over to our updated intake. To start, I'm going to grab onto this MAP sensor here. And if you grab the tabs, you can kind of pull them away from the sensor and then lift it straight up and out. Let's go ahead and put it on the backside of this intake here. Should just slide right in and be flush with the intake. Now, we're going to take one of our screws here, we'll start it in there, carefully screw it in. Okay. That bottomed out, just a teeny bit more, give it a nice wiggle, make sure it's secured. Next, let's go ahead and get this hose off of here. We're gonna try to get the hose off this plastic piece right here. You'll notice that the plastic piece is going to want to turn. So that might make it a little bit difficult. Just take a small pocket screwdriver or even a pick, come right in between the hose and the plastic, and just try to work it around a little bit to break it free.

Once you've done that, I'm gonna go ahead and try to twist and pull, see if I can get it off of there. There we are. Let's go ahead and put this over here. Let's get this off of there. Slide it right onto the piton there. Now, we're going to put the clamp up there. Okay. Give a nice twist, give it a nice tug, make sure it's secure. Let's start unbolting the fuel rail from the intake. As you work your way around, you might find bolts that look like this, rusted and rotted. You'll find that your socket just really doesn't hold on there. If that's the case, get yourself one of these twist sockets like this. That's going to help out. I'm just going to give it a couple of loving bonks. Get it off of there. I think we got it. Awesome. It's going to be time to get the fuel rails off of here now. Keep in mind that there might still be fuel located inside of the fuel rail system. So, if you take the little cover that we removed from the backside of the intake there, you'll notice that it slides right over, and it kind of holds on there. That's going to help keep the fuel from getting on your skin. Let's go ahead and try to pry up on it, just to break those fuel injectors free from the intake. It might take a little bit of force. To try getting this up off of here, I'm going to use some leverage. I'm just going to use a nice long screwdriver. I'm going to come across the intake and the fuel rail and just try to pry it up. There we are.

Okay. Do the same to the other side. Let's get this up off of here. We'll carefully flip it over. Now, we have a clear view of all the gaskets on our fuel injectors. Now you can either use a basic screwdriver or even a pick, just come right underneath this rubber O-ring. Be careful not to poke yourself, of course. Get it right off of there. Put that aside, do the same to all. It's going to be time to clean up these injectors. We want to make sure that the area where the seal's going to ride is nice and clean. I also like to clean up this head area right here, the area that's going to be pressed into the intake. We want to make sure that's nice and clean. And then, of course, one of the most important areas is right in the center area. You're going to notice those little dots. The little dots is actually the area that the fuel is going to get injected out of into the intake. So, that needs to be nice and clean. Clean it up. Make sure you pay special attention to those little dots like I said. Perfect. Let's do the same to all. You might notice the area where the seal is supposed to ride might have some built-up gunk in there. You need to make sure you get that out. Sometimes the rag with the cleaning solvent won't get it out.

It's going to be time to put our gaskets on the fuel injectors. You do not want to use your originals. Go ahead and replace them with some brand new ones. Take them one at a time. We're just going to slide them on and set them right down into that groove. Do the same to all. The next thing we need to do is lubricate these gaskets. To do that, I'm just going to use a tiny little bit of motor oil. I'm just going to put a nice little film around all of them. We have all those lubricated. Let's go and get this up onto here. I'm just going to carefully set it in. Make sure all of your injectors are going into the holes where they need to be. Check all eight to make sure before you press it down. This looks great. Let's go ahead and give it a nice press. Double-check everything. Make sure it's 100% seated. Grab four of our bolts here and we're going to start them all in before we tighten any of them down. Let's go ahead and snug them up. Okay. It's bottomed out. Just give it a teeny bit more. Do the same to all. Get this right off of here. Remove your 8-millimeter bolt. We're just going to go ahead and lubricate the seal right there. Use a little bit of motor oil, press it into the new intake. Grab our new bolt, go ahead and slide that in there. Start it in, snug it up.

It's going to be time to get the mounting bolts out for the intake now. You're going to notice there's a 10-millimeter head right here for the bolt that goes through, and then we need to remove this 10-millimeter nut. Something that's important to remember when you're removing this is you do not want to drop it into the hole in the intake. Get that right out of there. We'll do the same to all. Now, let's get the intake on here. It's important to remember that we're going to need to run this evap line in between the fuel line area and the intake itself. So just be prepared for that. Go ahead and go right up over the top. I'm just going to rest it down, get that hose off to the side, there we are. Okay. It's coming right down. This is looking great. Perfect. I'm just going to look around. I want to make sure that it's sitting flush with the engine. Looks like it needs to come down a little bit more. We also want to make sure that there's nothing underneath it. Make sure all your fuel injector wires are nice and clear. They're not going underneath the intake in any way. Also double-check to make sure that any of your other wiring that maybe runs along the backside of the intake isn't under there as well. I'm gonna check the other side.

There we go. That just fell right into place. Next step, we're just gonna use a tiny bit of blue thread locker on each of these bolts. Let's go ahead and start in all these bolts. Now that this is situated up on here and we have all the bolts started in, we're going to go ahead and snug them up. As we snug them up, we want to start from the center and we're going to work our way out. So, on the passenger side, I'm going to go with the center bolt. I'll just snug that up until it bottoms out. Okay. I'm not going to try to overtighten this. You definitely don't want to do that. Now, I'm going to go to the center on the driver's side. Now, we're going to go ahead and move to the fourth bolt on the driver's side from the front. Now, we're going to move to the second on the passenger side. Now, we're going to move to the fourth bolt on the passenger side. Now, we're going to move up to the second from the front on the driver's side. Now, we're just going to move straight up ahead to the front bolt on the driver's side. Now, let's move to the rearward bolt on the passenger side. Now let's move over to the rear bolt on the driver side. Let's move up to the front on the passenger side for number 10. Now, let's go ahead and do our first pass torquing these down to 44 inch-pounds. We're going to do that in the same sequence we just snugged them up in.

Now, it's going to be time to do our second pass torquing these down. We're going to torque it to 89 inch-pounds in the same sequence. Let's grab that fuel line, get that reattached ASAP. Make sure you give it a nice tug. Now, we're going to find our lock. When you install the lock, you want to put this side with the little hooky-dos into the line and then slide this side over. Just like that. Slide it in, lock it in. Give this a nice tug. You need to make sure it's 100% secure. Now, grabbing onto this line that we removed from the top area, we're just going to get this rubber boot off of there because we don't necessarily need that anymore. There we are. Let's take that line, slide it right inside this hose, and then put it down into this groove. So, now let's just pull this like that. And then we're going to take this, put it right up there, and then we'll reattach it. Nice. Let's get this reattached. Let's get the NOx sensor wiring reattached, click it in, give it a nice tug. You can see the hooky-do goes right there. Make sure it's secure.

Now, let's go ahead and reconnect in the MAP sensor. We have that located on the back of the intake. Click it in, give it a nice tug, make sure it's secured. Let's get the boot off this end of the intake right here. Connect in your hose. Now, it's time to start connecting in our injectors and make sure you lock it. Give it a nice tug, make sure it's secure. Do the same to all the rest. Now let's get this plate back on there. Just line it up with where it needs to go. Okay. All three of those are snugged up. Let's get our hose connected back on here. Give it a nice tug, make sure it's secure. Now, we're gonna install our three throttle body studs. Go ahead and start them all in. And then we'll torque them to 53 inch-pounds. Before we go ahead and put the nuts on, let's just go ahead and get this hose on there. If you can't get it on with your fingers, just go ahead and grab with some pliers. Just be very careful not to put a pinch into it. Let's grab the clamp and slide it right up where it belongs. There we are. Let's put on our three new nuts here. We'll bottom them out. Torque them to 89 inch-pounds.

Grab your connector, plug it back in, make sure it's locked and give it a wiggle. Let's get our air inlet back on here. When you slide this onto the throttle body, it's important to make sure that it's completely seated all the way around. You do not want any dirty air getting pulled into the intake. Let's get this side on there. All right. Snug up those clamps. Give it a nice tug. The engine cover back on, slide it all the way back into those hooks. Now it's going to be time to start up the vehicle. When we do that, there's a couple of things that we want to pay attention to. You want to make sure that you're looking at that fuel line. You don't want to have any leak there, obviously. You also want to listen for an audible hissing sound. If you hear a hissing sound, more than likely you left a vacuum line off. Lastly, just take a look, make sure you don't have a check engine light. Aside from that, take it for a road test.