fuel leak
 

This week I have noticed that I might have a fuel leak somewhere. When I have the heat on, I cant smell it. Although, when I turn off the heater, I can smell the raw gas smell coming into the vents. Sometimes its very light or doesnt smell at all, and sometimes it smells a lot. What could be leaking? Injectors? fuel rail leading to the injectors?

I'm getting a fuel pressure test on thursday so I will know more.

Thanks

Could be a fuel line somewhere. It could also be your cold start injector leaking at the fitting. Open the hood when you start it up and see if you can see any spots that might be getting fuel leakage.


Russ

yea i looked around when the engine is on and off to see if i can visually see anything leaking. so far nothing. but when im driving i can smell it, so i know there is a small leak somewhere in the engine bay and its getting into the vents.

Okay, so this morning I took it to my mechanic and he did a fuel pressure test on it.

Engine off spec 33-40: mine was 39
Engine on spec 23-30: mine was 29

He assured me that these numbers were fine for the car. I am trying to link this problem to another problem. If some of you remember my problem about hot restarts. So it turns out its not a fuel pump problem. He said that I could be running rich and that the fuel is dumping because of the mixture, which could cause the slight smell of gas. OR there could be a tiny leak, which he is going to check out next week for me.

In the mean time, I am going to search around and try and replace my MAF. It could be acting up. Sensor might be overheating, causing my rough starts and heavy breathing that the car has on hot starts.

Anyone have any input?

Check out the evaporation system. The charcoal can at the firewall on passenger side.

I'm not familiar with the evaporation system. I know where the charcoal can is. But how exactly does the evaporation system work?

Thanks.

evap system
 

yes mrnickleye is right. I had the same problem several years ago and it was because the canister was plugged. I ended up getting one from a junkyard cause the dealer here didn't have any. They considered it a non moving item and no one changes it anyways till I showed up asking about it.
The evap system is supposed to prevent fuel vapors from entering the atmosphere, by routing the vapors through the cannister to the intake manifold then on to the combustion chamber. If the smell is coming from the engine bay then the canister is plugged or one of the lines came off. The system is why the gas cap is sealed. On older cars you will notice the release of pressure from the cap when you fill up on a hot day while going on a trip.

Thanks for the info. I will check out the cannister tomorrow and check for some lines that could be loose. With our cars, the evap. system takes away that pressure that builds up from the cap? Is that right?
When I drive for a bit and then fill up, there is a lot of pressure being released from the gas cap. Normal?

No, the point of the system is to burn the evaporating fuel before it enters the atmosphere, thats why most states check the gas cap during the smog test. The pressure is from the fuel leaving the tank, the fuel returning (return line) and variatons in heat which changes the density of the fuel. You should almost allways have some pressure when you remove the cap, if you drive the car and remove the cap and don't have any then the cap is probably bad.
Depending on the config of your car e.g. egr etc. will determine the config of the evap system. My 87 N/A has no egr system so I run my canister directly to my throttle body because the bvsv valve on my thermostat housing broke.