[MadChemist]

The front driver's side drain on my 2006 LTZ's sunroof is not draining, causing water to leak into the cabin when it rains. Last time this happened, I ran a bicycle brake cable through the drain and unclogged it. Unfortunately, this is not helping this time. I've tried blowing compressed air at 35 psi into the drain as well, to no avail.

Is there anything else I can try to unclog it? If I pour water into the drain channel, it just sits there.

 

[1999 White C5 Coupe]

The front driver's side drain on my 2006 LTZ's sunroof is not draining, causing water to leak into the cabin when it rains. Last time this happened, I ran a bicycle brake cable through the drain and unclogged it. Unfortunately, this is not helping this time. I've tried blowing compressed air at 35 psi into the drain as well, to no avail.

Is there anything else I can try to unclog it? If I pour water into the drain channel, it just sits there.

A suggestion: My son had a 2004 Grand Prix GT2 (also a W-body car) with the factory sunroof. The front drain tubes would not drain. There was a TSB that applied to several car models including the Impala and Grand Prix to examine the drain tubes at the bottom of the car where it drained inside the fender, near the A pillar. The rubber hoses were cut off at the bottom "straight" with no angle cut. The tubes shifted slightly lower and were stopped from draining from the straight cut.

The TSB fix was to cut the bottom of the rubber tubes (inside the fender) at a 45 degree angle so they could not stop draining if the opening moved against the metal or debris. That fixed the drain problem.

I do not have a copy of the TSB (and no longer have the car to look at it) - but you may want to see where the drain lines exit at the bottom and see if they are pushed against the metal or are resting on debris (such as leaves and pine needles) that prevent the hoses from draining. We used to periodically clean out the bottom, inside of the fender (below the door hinges) to prevent problems with the sunroof drains.

Good luck - let us know what you find.

 

[MadChemist]

Thanks, I'll have a look tomorrow. Would I just need to peel away the sound insulation to find the drain tube behind it?

 

[sonjaab]

Look here......
Post #20
Download the pdf link with pics/diagrams/instructions

http://www.impalaforums.com/chevy-i...er-in-passenger-floorboard-2.html#post2178857

 

[MadChemist]

Thanks! I'm going to try pulling back the carpet and finding the access hole they mention. If there's no debris in the cavity and the end of the tube isn't up against the bottom of the fender, maybe I can try blowing air through the tube from the other end.

 

[1999 White C5 Coupe]

Thanks, I'll have a look tomorrow. Would I just need to peel away the sound insulation to find the drain tube behind it?

Yes - the flimsy jute pad that is inside the fender near the door hinges. If you move it up, you should see the drain tube exit the metal A pillar.

I have previously used a vacuum cleaner with a narrow wand tip to clean out debris at the bottom of the inside of the fender. I have also used "mechanical fingers" (the push plunger spring loaded type that you can use in an engine compartment to pick up a dropped tool) to clean out the inside of the fender where the water drains. It is impossible to get your hand inside there.

I live in the Midwest with lots of trees, pine trees and debris that finds its way into the inside of the fenders.

 

[MadChemist]

So I tried everything and it still won't drain! I pulled up the sound insulation behind the door hinges and there wasn't much debris. I cleared everything out, but it didn't help. While I was in there, I couldn't see the drain tube or any hole where it might come out of. Does the drain exit somewhere else in this model?

I pulled back the carpet and could not find an access hole, either. There's a hole next to the parking brake and hood release mechanisms, but it's too obstructed to use and I'm not sure that's the one referred to in the instructions.

Is there anything else I could try? The clog must be right at the end of the tube, since I can get almost the full length of bicycle cable through before it hits an obstruction.

 

[MadChemist]

Another update: I found the access hole, and I can see the bottom of the drain tube at the bottom of the A-pillar. Water is draining through the tube into the bottom of the A-pillar, but is not draining out of the A-pillar. There is a permanent pool of water just sitting in the A-pillar.

Where does the A-pillar drain? I can't find a hole to unclog it.

 

[1999 White C5 Coupe]

Another update: I found the access hole, and I can see the bottom of the drain tube at the bottom of the A-pillar. Water is draining through the tube into the bottom of the A-pillar, but is not draining out of the A-pillar. There is a permanent pool of water just sitting in the A-pillar.

Where does the A-pillar drain? I can't find a hole to unclog it.

Have a helper pour water in the RF sunroof tray drain and see where it drains on the RF of the car. That will give you a good idea where it should drain on the LF side.

 

[MadChemist]

I did try that, but it wasn't too much help for me. Water drains from a hole in the rocker panel, but I can't see any path from the rocker panel to the bottom of the A-pillar. When I inspect the bottom of the A-pillar (not the door jamb) through the hole behind the inside fuse box on the passenger side, there is no hole for water to drain from, yet somehow the water escapes. I'm wondering if it drains through the foam sealant or something. I'm also wondering if maybe the tubes aren't meant to be routed into the bottom of the A-pillar, but instead into the bottom of the door jamb somehow.

I tried using a wire and a compressor to clean out a bunch of leaves and grit from the hole in the rocker panel, but this didn't help. I ended up using some tubing to siphon water out of the A-pillar, but it's just going to fill back up next time it rains.

 

[MadChemist]

I finally got this fixed and I just want to post a quick update to help anyone who has the same problem.

So, in my 2006 Impala, the front sunroof drain tubes run down the windshield pillars to the bottom of the A-pillars and are not connected in any way to the door jamb. They just drain into the bottoms of the A-pillars. This is contrary to the factory service manual, which says that they should exit the A-pillar into the door jamb somewhere between the hinges. On my car, there is no hole for this to happen, so I assume the factory service manual is wrong. You can see the ends through two access holes:

Passenger side: Pull up the front carpet retainer trim (the plastic moulding at the bottom of the door frame that includes the cabin fuse box door). Then, release and pull out the fuse panel assembly to expose a big hole in the sheet metal at the bottom of the A-pillar. This is your window to see the black drain tube coming into the bottom of the A-pillar.

Driver's side: Pull up the front carpet retainer trim (the plastic moulding at the bottom of the door frame that includes an opening for the hood release lever). If you pull back a bit of carpet and insulation right behind the hood release lever, there is a small opening that lets you see into the bottom of the A-pillar, where the black drain tube terminates.

In my situation, the drain tube on the driver's side was not clogged. However, water would accumulate in the bottom of the A-pillar and not drain, preventing any additional water from draining through the front driver's side drain tube, leading to water leaking into the car through the sunroof opening. On the passenger side, I could see water pour out of the A-pillar through openings in the pinch weld/rocker panel.

Here's what I did to fix this:

For a better view of what I was doing, I removed the front fender liner, but this may not be necessary. I took a long Allen wrench (any sufficiently long, sturdy poking device will do) and stuck it in the drain opening where the pinch weld meets the front fender liner (the plastic that lines the wheel well). I tried poking it in at different angles until I found an angle (nearly straight upwards) where it went in fairly deep and I felt it pushing on some foam. This foam is body sealer. The A-pillars rely on gaps in the body sealer to drain, but if they become clogged or if there's too much body sealer from the factory, they won't be able to drain. I continued to push into the foam until I pierced it/removed the clogging debris and water starting running out. The sunroof now drains properly!

 

[jtrosky]

^^Great information! Thanks for sharing!

Sent from my HP SlateBook 10 x2 PC using Tapatalk

 

[sonjaab]

Congrats!

 

[hatzie]

The FSM sunroof pages are from the 2009 manual set. 2006 is obviously somewhat different.

 

[MadChemist]

I looked up the AllData and Chilton instructions for the 2006 version, and they were the same as the 2009 info in the link that was posted. For some reason, it's wrong.

 

[Coolgas]

I finally got this fixed and I just want to post a quick update to help anyone who has the same problem.

So, in my 2006 Impala, the front sunroof drain tubes run down the windshield pillars to the bottom of the A-pillars and are not connected in any way to the door jamb. They just drain into the bottoms of the A-pillars. This is contrary to the factory service manual, which says that they should exit the A-pillar into the door jamb somewhere between the hinges. On my car, there is no hole for this to happen, so I assume the factory service manual is wrong. You can see the ends through two access holes:

Passenger side: Pull up the front carpet retainer trim (the plastic moulding at the bottom of the door frame that includes the cabin fuse box door). Then, release and pull out the fuse panel assembly to expose a big hole in the sheet metal at the bottom of the A-pillar. This is your window to see the black drain tube coming into the bottom of the A-pillar.

Driver's side: Pull up the front carpet retainer trim (the plastic moulding at the bottom of the door frame that includes an opening for the hood release lever). If you pull back a bit of carpet and insulation right behind the hood release lever, there is a small opening that lets you see into the bottom of the A-pillar, where the black drain tube terminates.

In my situation, the drain tube on the driver's side was not clogged. However, water would accumulate in the bottom of the A-pillar and not drain, preventing any additional water from draining through the front driver's side drain tube, leading to water leaking into the car through the sunroof opening. On the passenger side, I could see water pour out of the A-pillar through openings in the pinch weld/rocker panel.

Here's what I did to fix this:

For a better view of what I was doing, I removed the front fender liner, but this may not be necessary. I took a long Allen wrench (any sufficiently long, sturdy poking device will do) and stuck it in the drain opening where the pinch weld meets the front fender liner (the plastic that lines the wheel well). I tried poking it in at different angles until I found an angle (nearly straight upwards) where it went in fairly deep and I felt it pushing on some foam. This foam is body sealer. The A-pillars rely on gaps in the body sealer to drain, but if they become clogged or if there's too much body sealer from the factory, they won't be able to drain. I continued to push into the foam until I pierced it/removed the clogging debris and water starting running out. The sunroof now drains properly!

Hey, I'm not sure if you're still active on the forum but I registered just to be able to post and thank you for this info. I had the same issue you were having with my 2006 Impala SS, the drains were clear but the water would pool up in the bottom of the a pillar with nowhere to go. I followed your advice and now the the water flows out the bottom of the car on the ground as fast as I can pour it in through the top. Thank you so much for posting your solution!