Exhaust or maybe fuel smell that is heavy when car windows are open and driving slowly or idling.

[christine33]

Hi,
I just purchased a 2001 A4 Audi Quattro 1.8 it has 95,000 miles on it and I've had it about a week. I've noticed that when the car is at a red light and idling, or when I'm driving slowly looking for a parking space etc, that there is a heavy fume smell when the windows are down. I've been using the AC due to the heat here in Connecticut USA but can't tell if it's really connected or not, my guess is that it isn't. I've been looking for help online but can't really determine the exact cause. It seems like a lot of questions have to due with a fuel smell inside the car but so far, my problem is only when the windows are down. If I shut them, I don't notice the smell.
Also, I had water drip onto my foot today from the accelerator pedal. Again, I had the AC on.
Thank you in advance, this is my first car and I'm nervous that this smell might be dangerous. Could it be exhaust coming into my car and I'll just pass out while driving? I know that sounds crazy but I'm just not sure because it is so strong.
I don't notice smell when I'm driving fast on highway but that could just be because it is blowing away.

Christine

[Zenerdiode]

Hi Christine, I hope you're enjoying your car.

Difficult to describe, but the exhaust (after catalyst) has a kind of sweet smell that to me is fairly bearable; but petrol (gas) has a much more raw smell. It feels like it's knawing at the front of your head. Try taking your car out for a run, then leave it idling and have a walk round the back to smell the exhaust fumes. I'm not talking on your knees with your nose in the tail-pipe, just try to catch a whiff. :) Then stop the engine and remove the petrol filler cap, waft the vapour towards your nose so you get a kind of "Yep, that's exhaust and that's petrol".

If you are smelling exhaust, there is a flexi-pipe just downstream of the CAT that can perish without hearing an exhaust blowing sound. Any leaks further back and you don't tend to smell them unless there is a door or boot (trunk) seal that has gone. Then it may be drawn in as you move.

If you are smelling petrol, the fuel lines are pressurised from the fuel pump just under the rear (passenger in your case) door, right to the front and the various fuel lines under the bonnet. There's a couple of reinforced rubber hoses that can start to perish and weep fuel.

The water dropping on your foot may either be the AC condensate drain is blocked (do you get a pool of water under the car when stopped on a humid day with the AC runnuing?) or the drains in the plenum chamber are blocked. (How much rain have you had in Connecticut?) The plenum is under the bonnet (hood) where the battery and brake servo sit. There are two drains that block (one either side) and the plenum can then hold GALLONS of water. When I had my B5 A4 and discovered this, I found the blocked drain tube, poked my finger through and you'd think I'd just pulled the plug out of the bath!!