Do You Smell Gas Diagnosing Fuel Leaks in Your Car Truck or SUV

Hey, friends. It's Len here from 1A Auto. Today I wanted to go over some quick tips with you for checking for a fuel leak on your automobile. I'm gonna show you a couple of quick places of where to look and then even what a fuel leak is gonna look like. Let's get started. Before we get started, I just wanna let you know, you can get right down there and you can click on that like button because I'm sure there's gonna be something you're gonna like. While you're at it, leave me a comment if there's something that you saw that you wanted to mention about. While we're still there, go ahead and subscribe and ring the bell, that way there you'll be kept up with all of our latest content. Let's get started.

So, as we get started on the vehicle, I just wanted to note that we could smell the fuel vapors coming from the front of the vehicle. That doesn't mean that I'm gonna stop looking once I get past finding the issue in the front. I'm gonna continue on to making sure I check that whole fuel system just in case there's multiple issues along the way. Let's get started right along the front. If you look up here, you're gonna see your intake. Generally speaking, underneath the intake, you're gonna see the engine, and more than likely, you're gonna be able to see the fuel rails right out in the open. There are gonna be times where you're gonna see fuel rails that might be buried underneath something. But that's gonna be one of the areas you need to look, because underneath the fuel rail, you're gonna have a fuel injector, and that fuel injector goes down into the engine. In between all those mating areas, there's gonna be an O-ring. And a lot of times the O-ring goes bad, it gets dry and brittle and even cracks and then it'll leak. If you see fluid or moisture around this area, odds are it's fuel. If you have a gloved finger, you can go ahead and touch on it, give it a little sniff, just be careful, I don't want you to get sick from it. If it smells like fuel, you found where one of your issues is.

We would follow the fuel rail all the way across. If you don't see any leaks, you just keep continuing. You have your crossover, it's gonna cross over to the other side of that intake/to the fuel rail. We can see the other side this has got a little bit more stuff burying it but if you look hard enough, you're gonna note that there isn't any leaks on this side. If we were to continue following the fuel rail, you're gonna wanna find where the input hose is. This is the area that's gonna be coming from your fuel filter/fuel pump. Comes down this way, right down in here. I can see a connector, you always wanna check any connectors you can see, make sure they're nice and tight, and they're definitely not leaking. That looks great. Let's get under the vehicle. So, now I'm just gonna follow my lines, I can see that they come underneath this plastic, it might be mounted, sometimes they're out in the open as well. So, what you would do is you just, of course, take out any of the mounting bolts, then you'll have a clear view of your lines. In this application, we can see the fuel filter clearly, you check those to make sure that those are definitely not leaking.

If you see anything that looks like residue that's coming down inside of the shield if you have one, more than likely there is a leak and you just can't see it. Follow all those lines as far back to the fuel tank as you can. They'll lead up and over the top of the fuel tank usually, and then they're gonna feed into where your fuel pump is. Might be a little hard to see on this one. You're gonna see that they get very rusted up top that could leak up there. You could also have lines that come out of it that rot out. The next thing you would wanna do would be to follow any other hoses that come out, you have your fill hose. If this is dry, brittle, and cracked, every time you fill your fuel tank, it's gonna come leaking out right through this hose and/or through the fuel filler neck, which of course runs up here.

If you look at your fuel tank, you might notice that it's plastic, or you might notice that it's actually metal. And it's covered with plastic, it might have a plastic cover. With that said, in between the plastic and the metal, a lot of times it'll accumulate dirt and debris and even moisture. That'll just sit in there because it'll have a hard time evaporating and it's gonna rot out the fuel tank. So, if you happen to see that you have rust building up or you can look through any of your holes inside the shield, and you see that it's rusted and rotted or even it looks like it was moist around it at one point, you might have a fuel leak behind the shield. We're doing well, we found where the fuel leak seems to be coming from. Now we need to thoroughly inspect the area. Before we go ahead and take the fuel rail off of here to check those O-rings, we need to make sure that we relieve pressure from the fuel system. There's a simple way of doing that, you would find the fuse for the fuel pump, pull that fuse, and then you would go ahead and get inside the vehicle and you would start that ignition. The car may or may not start at this point. If it does, more than likely it's only gonna run for a couple of seconds and then it's going to die out. The reason why it died out is because you've powered off that fuel pump, so the engine can't pull any more fuel from it. So, once you're sure that you have no more pressure inside of your lines, you can continue.

Now that we've relieved the fuel pressure, we're gonna disconnect the areas that are holding this fuel rail down, you just find the mounting bolts, take those out. Now that we have those mounting bolts out of there, we can wiggle this around. Generally speaking, you should be able to grab it and just kind of tug upward at the same time as moving it around and it should break free. If it doesn't, you could use something as simple as a pry bar or a screwdriver and carefully use something to pry up against and lift this up. If you're dealing with a plastic valve cover, it's plastic, it can break. So, don't apply too much pressure to these. I'm just gonna use my hands, wiggle that around. Awesome. So, the fuel rail is up, I can see my injector O-rings. I'm gonna press on this tab, and I'm gonna disconnect the electrical, pull that off of there.

Once you have all those connectors off, you can lift this up. Now we're gonna grab onto this with some pliers, give it a little twist and a pull. If you notice when you look down there that you have a lot of dirt and debris, you might wanna try to clean that out. You could use something as simple as a blowgun. If you do, just be super careful because obviously it could come back up into your face. Grab onto that with some pliers, give it a little twist and pull. I've got an O-ring down here and one right up there. Let's take those off and take a look at them. We've got the fuel injector over at the bench, we're gonna take a quick look at it. You wanna inspect the injector itself to make sure it isn't cracked anywhere. A lot of times what you'll find is that the plastic will actually have a small crack and then as it rots inside it'll spread further and you'll have issues. You wanna check right here. Obviously, that's just for electrical connectivity.

And then, of course, look down in here, you can see those little dots. That's actually where the fuel spray is gonna come out of. If those look like they're plugged up, or you can't even see them because there's so much varnish and garbage on them, you would of course want to either try to clean it or, of course, you could replace the fuel injector itself. For this video, we're looking for a leak. So, we're gonna continue on, we didn't see any cracks like I said. Let's grab these O-rings, this is the lower one, we're gonna be careful not to damage it. Now I'm just gonna take, if I had a smaller pocket screwdriver, two of them, I would just kind of spread it a little bit and I would take a peek to see if I see any cracks. Once you stretch it, you should see dry rot or cracks if it's bad. This one actually looks like it's in really great condition. I don't see any reason why I wouldn't wanna reuse it. Of course, before I put it back on I'll clean down the injector side and make sure it's nice and clean. If this is rusted and pitted obviously it's not gonna make a good seal.

Let's move along to that upper one. Oh, holy moly. Yeah, if you see an injector O-ring that looks like that, you need to go ahead and replace it. Okay? This is obviously very, very bad. When it comes to fuel leaks it's important to remember that fuel is flammable. That's what makes the car go vroom, of course, the mixture with the air and the fuel. If you have a fuel leak, and you can smell it, you definitely don't wanna keep on driving. A lot of people will say, "It's probably not that big of a deal, I can go to work, I can get out of work, I can go home, and then maybe later on this weekend I'll get around to checking my fuel leak." You definitely don't wanna do that because fuel is not only flammable, it's also combustible. In this case where we had our fuel leak on top of that engine, if we were to continue driving this, got that engine hot, fuel's leaking down, we could smell it, but, for some reason we didn't mind, the engine heated up even further. Maybe the fuel even made its way down to that boiling hot exhaust, you're gonna have a major issue and that's a safety issue. That's why we needed to do this video for you today.

Okay, so we found our fuel issue, it ended up being something as simple as an O-ring on our fuel injector. For you personally, you might have a different issue in one of those places that we went over throughout the video. If you can still smell fuel, and you checked all those areas for visual leakage, you might have a leak someplace else in the EVAP system. And if you liked the video, make sure you like, comment, and subscribe. While you're at it, ring the bell, that way there you'll be kept up with all of our latest content.

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