Engine smells like gas & gas fumes coming through A/C

Leros

Lifer
Jul 11, 2004
21,867
7
81
After running my car, the engine area of my car smells like gas. I can smell it just from getting out of the car (I don't have to go under the hood). If I turn the A/C or heater on, gas fumes come through the vents.

I'm not losing gas at an abnormal rate. I'm not going through a gallon a mile or anything ridiculous like that.

I don't know much about cars, but I can fix most stuff once I figure out what the problem is. I really can't afford to go to a mechanic.

Any suggestions as to what I should be looking for?
 

Leros

Lifer
Jul 11, 2004
21,867
7
81
Clearly. I'm not too familiar with the layout of an engine. Is there one obvious place to look for a fuel leak?

(I'm not complete incompetent, I swear! I've replaced my both my starter and my radiator by myself)
 

Tsavo

Platinum Member
Sep 29, 2009
2,645
37
91
Clearly. I'm not too familiar with the layout of an engine. Is there one obvious place to look for a fuel leak?

(I'm not complete incompetent, I swear! I've replaced my both my starter and my radiator by myself)

Smartassery aside, look at the fuel lines and check the gaskets of the fuel delivery system for leaks.

What car?
 

Leros

Lifer
Jul 11, 2004
21,867
7
81
Excellent. A few keywords to google is enough to get me started.

Its a 2000 Nissan Maxima.
 

boomerang

Lifer
Jun 19, 2000
18,883
641
126
Take whatever shrouding is removable off the engine. Carefully inspect the fuel lines. Their connections, the lines themselves, etc. If necessary start the car while watching for leaks.

Have a fire extinguisher handy. Don't ignore fuel leaks. Those cars you see burning on the side of the road infrequently are the ones where they ignored the leak.

We were on vacation on the Big Island. A good 45 minutes from the car rental at the condo we had rented. On our way to breakfast the first morning there, we smelled gasoline. I raised the hood and the whole engine compartment was wet. Called the rental company and they wanted us to drive it in. I told them I didn't think so. We argued some and they relented and sent a replacement out on a flatbed and hauled away the leaker. Don't discount gas leaks.
 

AMCRambler

Diamond Member
Jan 23, 2001
7,714
31
91
Sounds like a fuel leak and it's in your engine bay so not something to mess around with. You could end up with a fire. As the others have said, take any plastic shrouds off the engine and look at the fuel rail, injectors and fuel line for any leaking fuel. Found a pic of the Maxima engine and I highlighted what I think is the fuel rail to give you a place to look. Looks like there might be two separate rails for each bank of cylinders? Hard to tell from pictures though. Skoorb would know.

2000maximamotor.jpg
 

x-alki

Golden Member
Jun 2, 2007
1,353
1
81
If you start fiddling around with any of those quick connect gas hoses (not sure if thats the right terminology) be careful. They are under pressure and you could get a face full of gas.
 

Twista

Diamond Member
Jun 19, 2003
9,646
1
0
im proof of this. Dont drive the car.. and make sure u have a fire extinguisher near by... shit have 2. All you need is gas dripping on the hot header or the getting a spark from the battery and WHOOOSHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
 

RU482

Lifer
Apr 9, 2000
12,689
3
81
My car was doing this a while back (04 Impala 3400V6). Turned out to be a faulty fuel pressure regulator (the seal on it was leaking). replaced the part and the problem went away.

It doesn't take much gas at all for the smell to be strong. In my car's case, it was a few small drips a minute.

You should get in there and sniff around to find the source. Just don't cause any static!
 
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Bignate603

Lifer
Sep 5, 2000
13,897
1
0
It's definitely gas. And its not much, I haven't seen any leaks under the car (unless it has been only a few drops).

A small amount of gas can make a big stink, but this is still something you need to track down. Are there any spots that look wet?

I personally would start at the injectors and work back through the fuel system. Some injectors can get bad o-rings that will start leaking when things age so they can start to leak.

As many people have mentioned, you don't want to drive like this. If you can't figure it out or need the car working fast you'll be better off paying somebody to fix it than risk a massive engine fire.
 

exdeath

Lifer
Jan 29, 2004
13,679
10
81
I'm going to +1 on fuel pressure regulator. It's connected to a vacuum hose, and so are parts of your climate control system. That would be an easy path to create a strong smell in the passenger compartment. Try pulling those vacuum lines and sniffing for fuel odor.

Tiny fuel leaks are hard to spot since fuel evaporates almost instantly unless it's a large leak. If you can't find it visually, you'll have to use a UV dye leak detector kit.

Additionally, you might be able to run the pump and shut it off and listen for it.
 
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Leros

Lifer
Jul 11, 2004
21,867
7
81
I figure I should update this thread. It turned out to be a pinhole in a hose. Pretty simple fix.