romarpete

My 2011 HHR was having the common problem with a wet passenger side floor after it rained. Several previous forum postings suggested that a displaced "butyl patch" under the plastic cowl cover was a likely cause. When I removed my cowl cover I discovered that there was no rubber patch there at all. Apparently the later model HHRs have slightly re-designed sheet metal surrounding the big hole in the cowl that was supposed to remedy the problem without the patch. Nevertheless I decided to install my own patch made out of 1/16" rubber stock to cover the hole as some of the previous forum contributors have done. I wonder if any other HRR owners with the redesigned cowl sheet metal and no butyl patch have had the same wet floor problem or if I should look for another cause. BTW...I just bought my HHR and I am new to this forum and have found it very helpful. Many thanks to all the contributors.

Oldblue

Your wet floor issue could be either sunroof drain ( if you have a sunroof) or the wire harness boot to the passengers side door

https://www.chevyhhr.net/forums/prob...-solved-32427/

This



Should look like this only tighter

firemangeorge

Welcome to the site.

Butyl patches were only on the 06, some early 07 models. Not exactly sure which hole you covered on your's since there is no hole there where the butyl area was on earlier models.
I hope you didn't cover the hole under the cowl trim. That's the inlet for the fresh air to the cabin. I'll try to dig up some old pics I have or find the thread that shows when I had mine apart.

As far as leaks, sunroof drains seem to be the main problem for leaks.
Since you didn't say which model you have, I'll assume you have a sunroof ?

edit: Take a look at this thread. It shows the difference between a butyl and non-butyl HHR.
https://www.chevyhhr.net/forums/main...l-patch-58597/

Oldblue

Like this one, George

donbrew

Could come from a clogged A/C drip tube. The A/C runs when the defrost is on.

You can see the cabin air filter in oldblue's pics.

romarpete

Thanks guys. I will check the harness boot. And I have seen considerable condensation flow coming from the AC evaporator drain so I don't think it completely clogged but it may be a little restricted. What is interesting is that my car seems to have a 3rd variation on butyl patch area. Even though no butyl patch was in place (and no evidence that there ever was one) the opening in the cowl looks just like the pictures with the butyl patch except that there is a slight ridge formed around the windshield edge of the opening. But the size and shape of the hole looks just like the pictures with the butyl patch and nothing like the "hooded" opening in Oldlblue's photo. I wish I had taken a photo before I put the plastic cowl cover back on. I can clearly see the cabin filter under the hole but it looks a little different from the red HHR above also. I don't think (and I hope) placing an improvised patch over the hole won't affect cabin air flow.

donbrew

Explain: how you figure plugging the air inlet won't affect the flow.

If you can see the filter that is the inlet. (period)

As I recall my 2008 and 2011 did look different than FMG's, But, not like a 2006.

Here is a TSB on the subject: tsb 07-08-57-001G Is is too big for posting, GoOgle the number.

I am pretty sure it is somewhere in the "official TSB thread". https://www.chevyhhr.net/forums/prob...d-23231/page9/

romarpete

My reasoning is:
1) Since the only apparent difference between cars that came with and without the butyl patch is the slight change in the size and shape of the cowl opening, then the patch that I added is no different than cars that came with the patch to begin with and
2) There is still an air path from the area underneath the cowl on the passenger side (now covered by my new patch) to the drivers side of the cowl where the wiper motor and linkage is. There is a screened opening in the plastic cowl cover above the wiper assembly that will let in fresh air that can be drawn across laterally into to the passenger side space under the patch and above the cabin filter.

I am not sure that I explained that in a way that can be visualized but I did make sure that the cabin filter was not completely isolated when I added the patch (although the air flow might be slightly more restricted) . It is my hope that the patch will eliminate the direct path of water seeping under the plastic cowl cover, into the cowl opening and then into the cabin filter but still allow fresh air flow from the other side of the cowl where the screened opening is at the base of the windshield.

My main question was that if Chevy's redesign of the cowl opening without the butyl patch was adequate in itself to prevent water leakage was my modification was a waste of time because the water leak probably originated elsewhere.

firemangeorge

Ah. So you didn't cover over the opening at the cabin filter. You just covered up the sheet metal on the actual cowl(flat) area.
Yeah. Probably a waste of time. The redesign by GM seems adequate at keeping any water out.
Now if they'd only thought to put some sort of screen or vent cover on the firewall at the cabin filter. Would keep the leaves and debris from clogging up the filter.

donbrew

The original reason for the hole in 2006 was to install the fan after the ducting was installed. Then they made the fan integral to the ducting. I'm not sure when the redesign was done, maybe before production started.