Exhaust/Gas Smell

[mike662]

I have a slight exhaust/fuel smell when I let the car sit and idle with the fan on. I think it's coming from the front end and not the exhaust pipe leaking up through the wheel well. I had no idea where it comes from until recently I experienced a similar but much stronger smell in my friend's Honda Accord. It turns out she forgot to replace her oil filler cap after adding oil and the exhaust fumes were coming out from there and into the cabin.

I decided to check if my cap was maybe leaking but I can't tell for sure. When I removed it (first time I have done so) I noticed there was no rubber gasket there. Is there normally supposed to be one? If so, any suggestions where I could get one? Thanks!

 

[esnave09]

I think I'm having the same thing but I know mines from the exhaust pipe. You're absolutely sure you don't have an exhaust leak? Even the J pipe being separated from the catback?

 

[mike662]

I haven't excluded the possibility that it could be from the exhaust, I just haven't really spent the time to look as it's not a serious leak, only bothers me if I let the car idle a while before getting into it. I'll take a look at that pipe tomorrow thogh when I change the oil. Any easy way to tell if it's coming from there?

 

[rit14623]

A couple places where exhaust leak can occur in the P5.

The connection between the second catalytic converter and the end of the J-Pipe. There's an exhaust-spring connection. If the springs go weak, that can decrease the tightness and let exhaust out. Also, if the rear motor mount gets worn out (like mine, the rear end of the engine sags down. The angle of the J-pipe from the front to the back slopes downward so that connection to the second catalytic converter isn't straight, The donut gasket isn't enough to cover the leak. I replaced my donut gasket thinking it was a source of the problem. What a waste of money. I also tried exhause sealant, which just melted away. There's a noticeable increase in exhaust volume and air if there's a leak there.

 

[mike662]

So while trying to find something else under the hood, I found the source of the leak. It was so cold outside my exhaust was easily seen coming out from the connection just under the first cat. Anyone know a simple fix for this? It's not a huge problem so I don't want to spend lots of time or money on it, the only inconvenience is I don't heat my car up before getting into it since doing so could possibly be harmful since it smells like exhaust.

 

[rit14623]

So while trying to find something else under the hood, I found the source of the leak. It was so cold outside my exhaust was easily seen coming out from the connection just under the first cat. Anyone know a simple fix for this? It's not a huge problem so I don't want to spend lots of time or money on it, the only inconvenience is I don't heat my car up before getting into it since doing so could possibly be harmful since it smells like exhaust.

That's a relatively inexpensive fix. Replace it with a new gasket. That also leaked on me too. There's three bolts to undo.

 

[mike662]

Perfect, thanks!

 

[lowlevel]

Perfect, thanks!

You can actually feel these sometimes just by hovering your hand a couple inches away from the joints, and moving it around... I've seen people stuff a shop rag in the tailpipe to increase the pressure to make it easier to find. Sometimes you can just tighten up the bolts instead of replacing the gasket too... but usually they're all nasty.