Can a rear spoiler reduce exhaust fumes?

[karl]

I solved my stinky exhaust problems by pointing my exhaust tip to the side, behind the left rear tire under the bumper. Just cut a round hole and stick that supertrap out the side. I drive about 4,000 miles a month on the interstate in my 71 240 and it was killing me, problem fixed zero fumes.

Karl

[veritech-z]

That's a LOT of miles!

[rigez]

I did all the things posted here as well as replacing the return fuel lines and making sure the covers for the for the rear qtrs were sealed up

[Guest skar280]

Just a question for Michael. What would the effect of a primary spoiler mounted in front of the hatch at the back of the roof be? Would it create enough turbulence to minimize the back draft behind a rear mounted spoiler and perhaps assist with downforce (kind of like an older toyota supra)

[denny411]

The spoiler you are refering to doesn`t really generate downforce. It actually reduces lift by disrupting the airflow that is flowing over the hatch at speed.

if you search, there is a very long thread about this and other aerodynamic features of the s30.

[mario_82_ZXT]

I solved my stinky exhaust problems by pointing my exhaust tip to the side' date=' behind the left rear tire under the bumper. Just cut a round hole and stick that supertrap out the side. I drive about 4,000 miles a month on the interstate in my 71 240 and it was killing me, problem fixed zero fumes.

Karl[/quote']

Karl,

 

Dou yoou have a picture showing the exhaust tip job. Fumes are driving me crazy..

 

thanks

[Zmanco]

I too had done everything mentioned here (except BRAAP's) and still had fumes. I was especially frustrated that after the expense of changing the hatch seal that it was no better. In my case, sometimes things were great, and other times eye watering.

 

After a lot of noodling, I came up with the theory that over bumps the chasis was flexing and the rear hatch was moving around on the seal and at times, allowing gaps to form. This of course would allow the poor aerodynamics to vent fumes into the cabin.

 

I got in the back with the hatch closed and took a small piece of paper and tried to push it between the hatch and seal. Where there was a good fit the paper would just buckle, but there were a lot places where it slid right in with almost no resistance. That confirmed that even with the car standing still on my flat garage floor, the hatch didn't fit the seal very well. I'm sure some of that was due my not being sensitive to this issue when I glued the seal down, but since it was already done, I needed to try something else.

 

I did notice that I had more "gaps" on one side than the other, so I opened the hatch, and grasping the corners, "tweaked" it to get it closer. I then tried moving the latch mechanisms up and down (and forward and backward) and eventually found a combination that allowed the hatch to close rather easily, and where the paper buckled almost everywhere. This is how I have it now, and the fumes rarely come in.

 

My conclusion is that after you have done all the fixes, there is still some trial and error involved to get the hatch set "just right" to maximize how well the seal fits. I'll add that I still need to add a rear strut bar, and am hoping that will stiffen things up in the rear to help even more.

 

Note: if you think about it, the hatch is only held in 3 places: at the top left and right corners (by the hinges) and in the center of the bottom by the latch. That leaves a lot of room for it to move around, expecially when you consider how "flexy" the rear of the Z is.

[karl]

Mario, sorry I have not gotten back sooner. I do not have a digital camera, but I assure you that It works. You can also just put a 90degree smooth bend on the end of your current exhaust pipe and point It away from the car, this is what I did the first time I tried It. I drive alot to see my wife and kids and the fumes were killing me. I found the cure on accident while building a bike rack, I pointed the exhaust to the side so the heat wouldn't get to my mountain bikes shock and the fumes were gone. I had tried everything else listed here but nothing worked, now with all the driving I do I have zero fumes. I am getting ready to do a 7MGTE swap and am going to point the turbo exhaust out the same hole (I'm gathering rear end parts for the r230 swap, have everthing else, and with CLIFTONs help It will be awsome) good luck

[proxlamus©]

I have a c/f BRE wing now.. and it has not helped what so ever..

 

just FYI.. it has not helped me.. i have new tail light and hatch seals

 

[crashed240z]

I got my rid of my fume smell a little while ago, thought I would share my limited knowledge.

 

I replaced the hatch seal and the taillight seal. this didn't change the smell one bit. I found the leak after i put on this weird plastic valve cover and the engine started to pull oil into the carbs. you could see the smoke coming in from the interior vinyl hatch cover. I used lexan and some foam weatherstripping and sealed it.

 

Problem solved. the car's floors were not sealed nor the vapor line grommets. but I had No fumes at all. Maybe this breif info will help someone.

[denny411]

Has anyone considered putting stoppers at the outside corners of the hatch to insure that the hatch stays level? One could probably use the same stoppers that are used at the rear of the hood.

This would create five points of contact.

It might also make it easier to keep the hatch seams and gaps aligned for those of us who are interested in those types of nit-picky details.

 

I may do this myself since the whale tail might have a tendancy to make the hatch flutter at speed.

[col]

Hi just a sugestion for those of us that think fumes are coming from the hatch.To make 100% sure it was or was not a hatch leak I ran tape all round the hatch gap and go for a run. I did and the fumes are gone.looks like new seal and adjustment for me.Just a question for the airflow experts,How big would a spoiler have to be up on the roof in front of the hatch to detach the air from the lid minimising lift and reducing the fume problem?

[inlawZ]

really good stuff to know, ive been debating to get one or not, gonna get it!!

[josh817]

Yah uh.. problem. I have a rear spoiler but I have no idea how to install this thing.

Thats how thick the edge lip is, and the spoiler is hollow so how exactly do you mount it without cracking the fiberglass? I'd hate to say that you just bondo/glass it on...

[Bowtiez]

Ancient Problem. I had this problem in 1972 with my then new 240Z. It occurred when I had only the driver's side window down and the vents open. That seemed to suck the fumes in. With both windows up or the passenger side window down, there was no problem. The dealer said that was normal????

[jasper]

I read the entire thread. Very enlightening. However, I saw no mention of the exhaust witness marks......The smoking gun. Discolored drivers side tail lamps. The passenger side is always bright and shiny! The exhaust rolls right back up to the lamp.

[andre2000]

Is this an S30 problem in general? My Z31 had a fumes problem in the greenhouse but it went away after I rebuilt my engine and fixed some exhaust leaks.

[draft.phunk.amd]

wow, i never heard about this problem with any car. i hope i don't get any fumes in my 280z when it gets out of the shop

Edited August 24, 2009 by draft.phunk.amd
typos

[cygnusx1]

There is a clear path for fumes to enter the car. Up the "hatch latch hole" and into the cabin through the vinyl panel under the hatch. The vinyl panel is no where near airtight. Remove the vinyl panel, put a bead of sealant around the opening, seal off the opening with a sheet of plastic, reinstall the vinyl panel. This eliminates one more path.

[EddieBird]

mine is so bad...And I have like 3 different smells too!

 

I'm constantly reaking of fumes after even a 5 minute drive...