Worsening exhaust smell through windows

[ashwinearl]

Hi all,

2005 LGT wagon with 128k. 2 years ago I had AZP put in Cobb CATLESS (*correction I had written catted earlier) up-pipe and Cobb Catted Downpipe. They said that there would be a more noticeable exhaust smell with the windows down. And there was but nothing I didn't get used to.

 

More recently, the exhaust smell has gotten worse when the windows are down or moon roof open. It is to the point that my eyes get irritated.

 

Any suggestions on where/how to tell my local mechanic to investigate. They aren't a speciality shop. Up pipe/downpipe gaskets seem first thing to look at. Any other loose hoses that could be suspect?

 

Thanks.

Edited September 8, 2017 by ashwinearl

[MilesA]

Captain Obvious here. Exhaust leak most likely. Could be gaskets, could be an exhaust pipe rusting out, could be cat going bad. Do you hear any unusual noise?

 

BTW, your Cobb uppipe is probably catless, meaning you have just the one high-flow cat in the downpipe.

[ehsnils]

Check the rubber seals around the tailgate as well, windows down means that you get an underpressure in the cabin and it sucks in stuff from wherever it can get in.

 

Worsening exhaust smell may mean that the cats are going bad too.

 

That provided that you don't find any pre-cat leaks.

[ashwinearl]

 

BTW, your Cobb uppipe is probably catless, meaning you have just the one high-flow cat in the downpipe.

 

Yes , mistake on my part . Catless Cobb up pipe

[Holla]

You may want to look into plugging the hatch vents. When you open the windows, you're drawing air through the vents in the rear.

[ehsnils]

You may want to look into plugging the hatch vents. When you open the windows, you're drawing air through the vents in the rear.

Hatch vents shall be one way - at least when they are new - to prevent the backdraft from coming in. So they may be guilty as well. Easy to forget about them.

[ashwinearl]

Thanks for the hatch vent suggestion. In searching, I found some old threads on it.

http://legacygt.com/forums/showthread.php/catless-upp-now-have-leakii-180696.html?t=180696&highlight=vent+wagon+exhaust

 

 

http://legacygt.com/forums/showthread.php/relief-catless-dp-stench-finally-121365p3.html?highlight=Catless+stench

 

Where is this vent in the Wagon? Is it inside the tailgate. I haven't gone exploring yet removing the inside cover yet.

[bluesuby]

When the rocker arm covers start leaking oil, the smell of burning oil can be confused with exhaust.

[ehsnils]

The vent location varies a lot, but last time I saw one it was behind the rear bumper cover on the side of the car. It's not like they are visible today like they were on 80's cars and now they are hidden in obscure ways.

 

Look here: http://legacygt.com/forums/showthread.php/wants-see-my-vacation-pixi-6216.html

[Infosecdad]

The vents in your '05 wagon are in each rear quarters. You can take off the bumper to get to them or pull the inside covers. I chose the inside trim. You have to take out a good bit of the trim covers in the hatch area on each side and you'll see the black vents tucked down there, they are approx 10x5" or so. I blocked mine with some spare vinyl wrap I had left over. They aren't perfectly sealed, but they do stop a good bit of the smell that had been wandering into the back. There are one-way flaps for the vents, but as they age I think they are more open than closed.

[Max Capacity]

Those vents get my vote for being the issue.

[ashwinearl]

The vents in your '05 wagon are in each rear quarters. You can take off the bumper to get to them or pull the inside covers. I chose the inside trim.

 

Any suggestions for taking apart the rear quarter lower trim in a wagon? I tried in the past when accessing my Koni adjustments on the top of the strut but was only able to pull it back just a bit.

 

In the bumper removal instructions I see them point out two bolts that are covered by rubber grommets. Is the trim piece just held on by clips or are there more fasteners?

[Infosecdad]

I'm going to do it again in a couple days, I'll post a picture sequence for ya

[ashwinearl]

I'm going to do it again in a couple days, I'll post a picture sequence for ya

 

Very much appreciated. I've half heartedly tried to remove these piece when working on my stereo and accessing the adjustment on the top of my Konis and gave up quickly thinking I was going to end up ripping/breaking something.

[Infosecdad]

Here you go, hopefully it helps.

Let me know if you have any questions.

 

[ashwinearl]

I finally got around to trying this. Thanks so much to this community for providing information and courage no doubt to help me take apart things on this car.

 

When taking the trim off on the upper left/right of the tail gate, there is one more screw to remove. The plate that is above the lift gate latch is just held on by clips. By the seat belt, there is a pressed in plug that needs to be popped out to pull back the trim easier

 

When the trim is pulled back the vents are exposed.

 

I used some Zipp System Flashing tape from Lowes to tape them up. I had it from setting up Fatbike rims tubeless.

 

I'll test it out tomorrow and see if it worked.

 

Note that there is this green hose that sits in a port. On the left side, this hose had come loose. I am not sure what their function is. I plugged it back in where it is supposed to go

Edited November 2, 2017 by ashwinearl

[LuckyProfessional]

Yeah probably a definite exhaust leak at that point. Its not even that bad with my hogzaust, which is quite literally an exhaust leak.

[seanyb505]

I'm finally getting around to think I can lump this in with some other activities.

 

 

 

Bump to the top of my sub list lol

[ohno06gt]

I covered mine with duct tape last spring and it's starting to fail. It's very apparent with the windows down and leaves me stinking like exhaust.

 

I grabbed some rubberized asphalt flashing tape. Hopefully that does the trick.

[Pleides]

It sounds like the purpose of those to level out cabin pressure. I guess the health detriments of a catless exhaust being lessened are more important than climate control function, but keep in mind that no mod is without downsides!