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Top 5 Problems Chevy Avalanche Truck 1st Generation 2002-06

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Top 5 Problems Chevy Avalanche Truck 1st Generation 2002-06

Created on: 2020-05-23

This video discusses the top problems with the 1st generation Chevy Avalanche, which includes model years 2002 to 2006.

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In this video, we're going over the top five problems on this first-generation Chevy Avalanche.

Now, there's nothing wrong with this vehicle, there's nothing wrong with owning one or buying one. These are just the top five common problems with this vehicle. Number one, fading plastic. Because it's an Avalanche, especially the first generation and the earlier ones, they had plastic all over. There's plastic on the sides, plastic on the bumpers, and even plastic up here and they all fade.

Now, a lot of people know about using a heat gun and heating up the plastic. This is actually for the tonneau cover that comes with the vehicle. And if you use this, it actually melts the plastic a little bit. Now you could probably get a wider adapter for the heat gun to help out a little bit, but as you can see, this takes a long time to do. I did this little section earlier. It probably took about five minutes just to do that little section.

Or you can use something that's gonna be a little bit easier, some trim restoration, and just put this on a towel. And if you watch this, it goes on pretty easy. Just wipe it in, just a little more. You let that sit for about five minutes and then you go back with a microfiber towel and wipe it away. All right. So that looks pretty good. Now this area alone only took about five minutes. So you could see with the heat gun, you'd be here for at least 20 to half an hour.

Number two, fuel trim codes, specifically lean codes. Now the engine needs a air-fuel mixture of 14.7 to one to run perfect. That will give you the best fuel mileage and best performance. Now how it measures that is through the airflow sensor, the mass airflow sensor, and also through the O2 sensors. So when air goes past here, it tells the computer how much, and then it's gonna spray so much fuel. And then it's gonna measure that output through the O2 sensor and that will adjust accordingly. Now, if that mixture's off, if there's air getting into the intake that's not being metered by the mass airflow sensor, that's when you're going to get that code. Most likely it won't give you a drivability issue, but it could potentially give you a misfire and then you'd feel something. You'd feel a little rumbling in the engine. You'd get a little vibration, but normally you don't feel anything.

Now what could be going wrong is the intake snorkel could be loose, it could be air getting in here. The intake gasket actually underneath this intake plenum, the plastic plenum, those breaks sometimes so those would need to be replaced. And also you could have sensor issue which is giving you the same condition. You could have a bad mass airflow sensor or even a dirty mass airflow sensor, or an O2 sensor causing the same issue.

Number three, front impact sensors. Now you may get a code in your airbag module that has a code saying something's wrong with the front impact sensors. And they're located if you take this shield off, right attached to the frame right here or the lower radiator support right there. There's one on this side and there's one on the other side. Now it's always good to check the wiring, check the connector for any corrosion and stuff, but normally they corrode on the inside. And it's always a good idea to replace these in pairs because if one's corroded, the other one's not far behind. Just disconnect the connector. Make sure you disconnect the battery before you do this. And then there's a bolt on the bottom. It's a 10-millimeter bolt, I believe, and same on the other side. And then there's a slot. You have to slide it out of the slot.

Number four, the encoder motor. Now you may have a four-wheel-drive issue where you get a code saying basically the encoder motor doesn't know where it is. The sensor in there may be faulty and you can replace just the sensor or you can replace the whole encoder motor. It's a lot cheaper to do just the sensor and it's not that difficult. You just pull it off, pull it apart. As long as there's not a lot of corrosion inside there, you can do just the sensor. So some of the symptoms you may find with the encoder motor being bad or the sensor the four-wheel-drive won't work and also you'll get a code in the four-wheel-drive module.

Some other things to check if you're having problems with that, check the connector and the wiring. Sometimes the wiring does get messed up. There is a wire right here it goes over. Might find corrosion in some of the wiring and also under the hood. Underneath the fuse box, a lot of times, mice like to get in there and chew some of those wires and some of those circuits are related to the encoder motor so check those out, check your fuses.
Another good thing to check is the grounds. The grounds are located right here. Just want to make sure those are nice and tight and if you have to loosen these bolts up, clean up the grounds and tighten them back down and just double-check.

Number five, the EVAP vent valve. It's located right here right next to the fuel tank. On the backside, there's a connector right here. You always want to check the connector. If you have a circuit code, you want to take a look at those connectors real good. Make sure you have power and ground there. You can put a test light in here and activate it if your scan tool gives you that ability, check that out. Most likely that's the culprit. And also sometimes the newer vent valves look a little bit different, but they still work the same way. Now, whenever you get an EVAP code unless it's a circuit code, but you should always double-check the fuel cap. Make sure it's tight, make sure it's not loose, and make sure the gasket looks good. So this is part of the EVAP emission system. Now, this is gonna vent fresh air into the EVAP system. If there's too much pressure, it opens up the vent. Normally it is open and when it activates, it closes it so that it can put a vacuum on that system. It has to do with the vapors in the fuel tank and you want to not have those vapors go into the atmosphere. Now, if this goes bad, you're probably just gonna get the code. It's not gonna give you a drivability issue. It's just gonna be an emissions code and it won't pass the emissions.

And we have a bonus one for you. The rear tailgate handle. Now, sometimes you go to close the tailgate and it will just bounce. It won't close completely. What that is is the tailgate handle itself is frozen and it'll rust together sometimes and keep the rods from releasing so that it's able to close. Even this one's a little bit loose, but what you can do is take these three bolts out and these two bolts too. These two bolts go to the cover. Take the cover off. There's some pins that hold that on. Take the handle off, pop the rods off, put the new one on, put it back together and you're good to go.
So those are the top five problems that we have found on this Avalanche. Now we sell most of those parts at And if you enjoyed this video, make sure you subscribe to our channel, ring that bell, turn on all notifications so you don't miss any of our videos.

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