HOW TO: Repair Passenger Taillight leak- 98-02 Firebird/WS6
I didn't see a walk-thru thread for this, so I took a few pictures and wrote one up real quick. I hope I'm able to help someone, and maybe the Mods will deem this as "sticky worthy" :)
The very first thing I noticed when I bought my 98 Firebird was that the passenger side taillight was darker than the driver's side. The difference was so much that at one point, I thought maybe the passenger side was tinted, or I had bulbs burned out. A little research soon turned up the reason- water leaking past the silicone seal that is around the perimeter of the taillight, and ultimately tarnishing and destroying the reflective surface inside of the taillight. The constant water exposure quickly destroys the chrome coating on the inside of the taillight, effectively and drastically reducing the amount of light that can be reflected and projected thru the red lens of the taillight. A surefire sign that this is happening to your vehicle is fogging or moisture on your passenger side back up light. (This is the clear, round area of your taillight, just under the hatch, as seen below). Note the water droplets on the inside of the clear plastic, and of course, the darker taillight. Also seen is calcium deposit below the backup light- another sign of what's happening.
http://i265.photobucket.com/albums/i...0218121249.jpg http://i265.photobucket.com/albums/i...18121256-1.jpg
I will quickly walk thru the steps I took to repair this problem. Overall, I would give the job a 5 on the difficulty, and say that anyone who has basic mechanical knowledge is capable. The hardest part, honestly, is being patient. The job from start to finish took me about 6 hours, but I went really slow and to not break anything (and took lots of breaks!) Also, if anyone has any questions, feel free to message me or post in this thread.
First, you will need to gain access to the nuts holding the taillight housing in. Pop the hatch/"trunk" and pull the rear passenger side panel out- This is the large plastic panel where your speaker is mounted. There are 3 large screw heads, marked "Lock/Unlock". Turn those to the "unlock" position and raise the panel out, gaining access to the spare tire area. Set this panel aside for now. Remove the jack and the spare tire- this is necessary to gain access to the taillight.
Pull back the carpet a little and you will see 5 plastic wing nuts- 4 of them are behind the main part of the taillight, and 1 is toward the fender (behind where the spare tire is stored).
http://i265.photobucket.com/albums/i...0218121252.jpg
Remove the 5 wing nuts while keeping your hand on the taillight so it doesn't fall as you're loosening it. Once the wing nuts have been removed, you can pull the taillight out a little to expose the bulb sockets. *Don't pull the taillight out very far, or you might damage the wiring or sockets.*
http://i265.photobucket.com/albums/i...0218121257.jpg
While holding the little tabs, turn gently on the bulb sockets, removing them from the taillight unit. Once all of these are removed, the taillight can be removed from the vehicle, and taken to your work area. I suggest somewhere clean, as the plastic can easily be scratch, screwing up the appearance of the taillight.
The taillight is actually 2 pieces, that are siliconed together. You can see the (crappy) bead of silicone in the picture below. It runs all the way around the taillight.
http://i265.photobucket.com/albums/i...0218121315.jpg
Starting at the small end of the taillight, use a heat gun to warm the seal in-between the two pieces of the taillight. I cannot stress enough, WATCH THE HEAT closely, as you don't want to melt anything! The entire unit is plastic and can be melted easily with a heat gun. I held the gun aprox 5 inches from the surface, continuously moving it back and forth to keep the heat evenly distributed. Once the joint is good and warm, gently use a medium sized flat head screwdriver to pry the two pieces apart. You just want to pry far enough so that you can slip a small wedge in-between the two pieces. See below.
http://i265.photobucket.com/albums/i...0218121416.jpg
Once you have successfully inserted a wedge in-between the two pieces, you can continue to use the screwdriver to slowly pry the two pieces apart, inserting wedges as you go. Remember that you will need to continue to warm the area you are working on with the heat gun as you go. I can't stress enough to GO SLOW, and don't pry too hard with the screwdriver. The plastic on the taillight has aged and you are warming it, making it even more brittle. So, GO SLOW, yo! This is the most time consuming part of the whole job. You may also need to use a utility knife to cut thru some of the silicone as you're heating it. (It gets pretty thick in areas).
http://i265.photobucket.com/albums/i...0218121417.jpg
Continue working your way around the taillight, inserting your trusty wedges as you go. I would suggest starting at the end of the unit, as I did, and working your way a little down the top of the unit, and then a little way on the bottom side of the unit, eventually ending up at the end of the unit (where the backup light is). I can tell you that this is the area where the silicone is the thickest, which is why I saved it for last. Extra time and patience may be needed in finally separating the two pieces...but be patient. It will happen!
http://i265.photobucket.com/albums/i...0218121500.jpg http://i265.photobucket.com/albums/i...0218121505.jpg
Hopefully by this point, you have successfully separated the two pieces, and have set the red lens aside as so it doesn't get scratched or even worse, painted.
http://i265.photobucket.com/albums/i...0218121607.jpg
The first thing you will notice is how dark the chrome is inside of the taillight. This is due to water exposure and is the reason why this taillight is darker that the other (and also the reason you have ripped your beautiful car apart!!). You can see the difference in the chrome finish in the photo below.
http://i265.photobucket.com/albums/i...218121620a.jpg
The entire piece will need to be cleaned. All of the leftover silicone will need to be removed from the unit, in order to make a good seal later. The easiest way I found to remove it was with the heat gun and a utility knife. I was afraid to use any kind of solvent to do this, as I wasn't sure about it damaging the plastic. It's slow going and frustrating this way, but it's effective. It's very important that you remove as much silicone as you can, in order to prevent future leaks.
Once the silicone has been removed, clean the entire unit with water. I also used a soft brush to knock any loose dirt or debris off. Let the piece dry and then go over the inside surface with a piece of fine sandpaper or steel wool. This will give the paint something to stick to. (Note, don't accidently scratch the outside of this housing, as the top side of it is visible when you have your hatch opened). Once you've hit it with the steel wool or sandpaper, give it a good wash under water again as to get rid of the dust or other debris left by sanding it. Once the piece is dried, I suggest wiping the surface down with rubbing alcohol as to remove any oils left by your fingers. This will give the paint a clean surface to stick to.
Once the housing is cleaned, you can now tape around the edges with masking tape, so you don't get paint on surface area that doesn't need paint. As seen below, I just ran it around the edges, and along the top side of the housing, as this area is seen when your hatch is opened. Be careful not to touch the inside as it's ready to be painted. By this point, you should be cleaned, prepped and ready for paint.
http://i265.photobucket.com/albums/i...0218121741.jpg