Gas fumes during idling

impala

#1

I have strong gas fumes during idling or warm up. The fumes disappear once the car is moving and warm. The garage could not find the source.


#2

Likely a manifold exhaust leak. You’d hear this as semi-loud sputtering sound ahead of the cabin.


#3

There could also be a problem with the evaporative control system.


#4

I should have said–it is a gas smell and not exhaust


#5

You need to fill in a lot of missing details, including:

Model year of the car
Odometer mileage of the car
How long ago you bought the car

I am asking these questions because it is possible that you are just smelling the effects of the richer gas/air mixture during the first stages of warm-up on a cold morning, coupled with the catalytic converter’s very low level of efficiency when it is cold. If you have had the car for more than a very brief period of time–is this symptom something new, or has the car always exhibited this symptom?


#6

2005 Impala–54,000 miles–I recently purchased it from family–the car had been driven less than 3,000 miles in the past 14 months.


#7

Before starting the car for the first time in the morning, open the hood and locate the fuel injectors. Start the engine and look closely at the base of the injectors for indications of gasoline seeping around the seals. I have seen several vehicles that would develop minor leaks there when the temperature was below 40* and the leak would quickly disappear when the engine warmed up. And of course, the liquid that had leaked would quickly evaporate when the engine warmed…