Odor coming from AC vent at idle

[MrFiveOh]

So I recently pulled vacuum and replaced 134a in my truck. It cools better than before. The issue I have run into is an odor coming from my AC vent at idle and only with the AC on. It almost smells like gasoline, the engine bay doesn't smell like gas or anything out of the ordinary. Once I start driving it goes away. I literally just started and I haven't messed with fuel lines since installing new hoses and fuel pump a couple months ago.

Thanks

[bd]

Is this on the 74 Smurf?

Fuel leaks can occur at any time.  Might just be coincidence that the A/C was serviced.  First and foremost, perform a careful inspection for any evidence of fuel leakage.  Don't neglect looking at and around the fuel pump, including the vent in the side of the pump.  Take a sniff and feel of the oil off the engine dipstick, too. 

Sniff the vents with an appropriate leak detector to determine whether a small refrigerant leak exists from the evaporator core.  How long has it been since the A/C last functioned?  The odor might be from dust accumulation in the vents that is "activated" by condensation off the evaporator.  Make sure the evap housing drain isn't plugged, causing condensation to collect inside the housing.  You might need to freshen the ducts with an aggressive spraying of Ozium and/or remove the ducts that are accessible and wash them out with soapy water.  Chemicals used during A/C service may have found their way into the ducts or evap housing, especially if the cork tape sealing the evap core pipes is missing or has deteriorated.  Early evidence of a heater core leak is another possibility.  Pressurize the cooling system to 20 PSI with the engine off and see if it maintains pressure. 

[MrFiveOh]

Is this on the 74 Smurf?

Fuel leaks can occur at any time.  Might just be coincidence that the A/C was serviced.  First and foremost, perform a careful inspection for any evidence of fuel leakage.  Don't neglect looking at and around the fuel pump, including the vent in the side of the pump.  Take a sniff and feel of the oil off the engine dipstick, too. 

Sniff the vents with an appropriate leak detector to determine whether a small refrigerant leak exists from the evaporator core.  How long has it been since the A/C last functioned?  The odor might be from dust accumulation in the vents that is "activated" by condensation off the evaporator.  Make sure the evap housing drain isn't plugged, causing condensation to collect inside the housing.  You might need to freshen the ducts with an aggressive spraying of Ozium and/or remove the ducts that are accessible and wash them out with soapy water.  Chemicals used during A/C service may have found their way into the ducts or evap housing, especially if the cork tape sealing the evap core pipes is missing or has deteriorated.  Early evidence of a heater core leak is another possibility.  Pressurize the cooling system to 20 PSI with the engine off and see if it maintains pressure.

Yes on the 74. I've had ac running for the past year. It was only,out of service to pull vacuum and refill with 134a. I did the service this past Sunday and it didn't smell at all, on Tuesday I parked my truck at a decline (nose down) before I went to my class. after class I started it up and that's when the smell started. I don't have a plug per say for the condensation to drain but it most definitely drains, I can literally see it stream down the bottom of the ac box and down the wheel well.

[MrFiveOh]

Oh and when i did pull vacuum i had it set after for 20 min and it held around 26-25 psi

[MrFiveOh]

Well i figured out my problem, previously i would check the engine bay when the truck was already warmed up, well i checked on a cold start and i found my fuel pump was leaking at the weep hole. Good thing it has warranty.

[bd]

I had a feeling that was what you would find.  Let a drop of oil from the engine dipstick land on a clean, dry fingertip and watch it.  If it holds together in a tight circle, it's okay.  But, if it tracks out along your finger ridges, the oil is saturated with gasoline and needs to be replaced, along with a new oil filter, after the fuel pump is replaced.

[MrFiveOh]

I had a feeling that was what you would find.  Let a drop of oil from the engine dipstick land on a clean, dry fingertip and watch it.  If it holds together in a tight circle, it's okay.  But, if it tracks out along your finger ridges, the oil is saturated with gasoline and needs to be replaced, along with a new oil filter, after the fuel pump is replaced.

Thanks for the tip. Its time for an oil change anyway, wifey's car need it to so good timing i guess. Luckily i only drove it a couple days like this to and from work.