Exhaust Fumes: Do you get them, and how is your car set up?

[strotter]

OK, it's time to apply some scientific method to the exhaust fumes problem many of us suffer from. Below are a series of questions about your car, its condition, and your driving habits. Perhaps we can isolate the solution by isolating the problem. Folks without a fumes problem should especially respond. We need to know what you're doing right!

 

1a. Do you get exhaust fumes? y/n

 

1b. If so, under what conditions do you smell exhaust? (include vehicle speed, position of window(s), time of year, type of traffic, and type of road surface):

 

1c. Also if so, under what conditions do you *not* smell exhaust?:

 

1d. If you now smell exhaust, was there ever any time you *did not*? (before replacing muffler, before lowering, before painting the car, etc):

 

2. Year of your Z:

 

3. General condition of body:

 

4a. Do you have any bad hatch/door/window seals? Which ones in particular?

 

4b. Do you have any bad firewall seals, such as around wiring cutouts (can you see daylight)? If so, which?

 

4c. Are all the air-gaps around tail-lights and fuel hoses sealed? If not, which?

 

4d. Are all air-gaps around side-marker lights sealed?

 

5. Are all the air outlet vents present and open? If not, which have you blocked?

 

6. Is there anything non-stock about the underbody of the car? (i.e., dual exhaust, damage to underside, missing drain seals, missing close-out panels, etc?):

 

7. Has your car ever been hit so as to potentially affect its structure? If so, how and how severely?

 

8. Is your ride height stock? If not, how "lowered" is it?

 

9. Are your tire/wheels stock? (Tires stock height/stock width? Wheels stock diameter/stock width? Stock offset?):

 

9b. If you have non-stock wheels, are they more or less "open" (in terms of airflow, just eye-balling them) than stock?

 

10. Does your car have an air dam? If so, how low is it? Does it "wrap" around to the sides of the fenders?

 

11. Does your car have a spoiler? If so, what type, how tall, what angle to the rear of the car?

 

12. Does your car have a non-Nissan exhaust system? (I'm thinking about the muffler and exhaust "tip" here). Please describe the size, placement, and exhaust tip length, diameter, and angle of the opening.

 

13. If you've fixed the problem, what change did you make? How complete was the solution?

 

That's enough for now. Whew!

[strotter]

Here's a handy template for you to fill out the "form": just copy the numbers below, paste them into your response pane, and fill in from there. Have fun!

 

1a:

1b:

1c:

1d:

2:

3:

4a:

4b:

4c:

4d:

5:

6:

7:

8:

9:

9b:

10:

11:

12:

13:

[strotter]

I'll go first:

 

1a:Yes

1b:Speeds under 40, windows open all the way. Only driven in winter, cool cloudy weather. City and secondary roads.

1c:Higher speeds, windows closed.

1d:Always smelled it.

2:'72

3:Good. New paint, body straight.

4a:New hatch/door seals, Nissan. Old factory window felts (torn up).

4b:Some sunlight visible. Mostly siliconed shut. Several small openings on driver-side firewall. Wiring holes still have gaps.

4c:All siliconed

4d:All siliconed

5:All Open

6:Missing drain seal, passenger side. Lots of rust holes cut out/welded shut. Both passenger and driver foot-wells show impact damage. Dual exhaust.

7:Severe hit, passenger side. Several panels replaced. Severe hit, driver's side rear. Much bondo. Shape is OK.

8:Lowered, 2" or so.

9:Tires about 7" wide patch. Stock height.

9b:More "open" than stock (brake structures clearly visible).

10:Low airdam, 2.5" off road, wraps to front of wheel openings.

11:"Factory" style spoiler, one-piece.

12:Dual exhaust to 2-into-1 muffler w/ 3" long tip, 2.5" diameter. Cut off square to pipe. Did not extend past the bumper.

13:Improved it *much* by adding 5" long sleeve over the exhaust tip extending past bumper. 45 degree cut-off.

[Pop N Wood]

Man, thats too much work.

 

There was a recent thread on exhaust fumes that covered it very well. It was the one where I think ZR8ED was building diffusers underneath his car. In the final post, one member did a series of steps to get rid of the fumes in his car (something about a car bong and silicone caulk). In the end he bought an $8 exhaust tip extention and that cured his fumes problem.

 

Try a search and find the thread.