Sorry if I'm not more specific, but I've had the truck less than a week and I'm not too familiar with all the bits under the hood yet. The noise is odd, like a diaphram lifting (kind of a quiet honking noise.) It is coming from an area between the electrical box (aft of the battery) and the brake resevoir/master cylinder. The spot where the sound is coming from has two ?diaphragms? on top of a black box, with several vacuum lines connected. Not sure what any of this assembly does yet, but when I shut off the engine, I heard an intermitent noise coming from this area. It is over 20 minutes now, and still doing it. It gives a honking noise every 5-10 seconds which lasts a second or two.
Not sure if related to this above problem or cold ambient temps, but my battery was nearly dead after having truck parked for 4 days. Could be weak battery, and/or the remote starter's blinking LED on dash. Speaking of starter, I have no remotes for the truck, and I looked under dash to see if I could identify the make/model of starter so I could obtain new remote. All I see is a "290i For use on vehicle with automatic transmission only" along with what looks to be a bird inside a circle logo. Can anyone help identify the remote starter I've described?
Oh, and more good news; looks like I've got a coolant leak. Boosted the truck with my Protege to get it running (-22 C ambient temp) and after moving it into garage (to hook up battery charger), noticed a green coolant spot on the ground about the size of a saucer. I looked all around with a flashlight to try to identify the source, but with no luck. My pal is a service manager for a dealership nearby, and has volunteered to put some dye in the coolant to identify the leak better with a blacklight. Just to satisfy my knowledge, how much can I expect to pay for a water pump or radiator? The rad looks pretty shiny, so I'm guessing it has been replaced once already. It looks like the front end suffered some damage at some point. Fenders and hood are original, but rad support is pushed back at lower level, somewhat.
Also looks like master cyclinder is new. Brake resevoir has new brake fluid in it. As an interesting side note, one of the reasons I know the previous owner cared a great deal for the vehicle is that all body parts have security identification in case of theft, and because the hood prop has black electrical tape wrapped around the end to prevent marring the paint of the hood. One of those little details that tells a story....

 

its your evap system depressurizing...just live with it. when i noticed it i thought there was a bomb in the motor

 

Mine does the same thing... A friend of mine's runner did it also. doesn't seem to cause any problems yet. I have had my truck for almost 2 years and it has done it from the beginning.

I would be interested in a cheep fix if anyone has any ideas.

 

The dealer has a cheap fix for it. It's about $20 if I remember correctly. And yes, it's just the EVAP system from the fuel tank.

 

Thanks. The thought HAD crossed my mind that it might be evap related, but the contraption I was looking at seemed too complex and high up in the engine bay, so I dismissed it in favor of something else...... With a new (to me) vehicle, I'm paranoid about every little noise it makes, until I get to know it better and develop a layer of trust. I just stuck my head into the garage, and it is still doing it; probably started as soon as the fuel in the tank warmed up (does the fuel pressure regulate using a bypass line back to the tank?) and will continue as long as the vehicle keeps warming up inside the garage which is still just above freezing temp. Funny little quirks you get to learn about with each and every vehicle you own, huh?

 

Yes, I had the same concerns when I got mine. I may have even created a thread about it a while back. I figured out what it was by sticking my ear down close then pulling the line off in the middle of a "snore." Sure enough, it stopped. Only problem is I started to smell fuel. Not good. I put it back on ASAP.