2004 Explorer starting rattling under the hood

[Tranquillity]

Hi everyone, I'm new here. I've been searching these forums for a while now and have found them very useful, thank you. I am not a mechanic nor have the ability to fix anything myself at this point in time. I've mostly used the site to try and narrow down possible problems and to guard myself against people trying to take advantage of me. My most recent search is about a rattling sound I just started hearing under the hood of my 2004 Explorer. First, some background info:

-2004 Explorer V6 4.0
-bought in October 2012 with 112k miles, now has 122k
-before moving across the country in August 2013 (Indiana to California), it was serviced: spark plugs and wires were replaced, and the right rear wheel bearing as well. No other issues were found.

Now, as of this past Saturday, I started hearing a rattle under the hood. Like others have said, it sounds like someone shaking a can of spray paint with the ball rattling inside. I heard it as my wife was driving very slowly through a parking lot, after driving on a freeway (50-60mph) for about 5 minutes. It's pretty subtle.

Needless to say, the sound freaked me out, but then I didn't hear it the next few times we drove the car, until today. So far I'm only hearing it at startup/idle, and very low speeds.

After reading another post (http://www.explorerforum.com/forums/showpost.php?p=2988684&postcount=16), I realized that I have the very same hissing sound coming out of my car as mentioned here. It happens about half the time, and is coming out of the right side of the car under the hood. The car may have had this problem when we bought it, as I have never noticed a difference in performance.

At this point, what should I do? I have to mention that I am currently out of a job and in some serious debt. I need to weigh my options before I throw more money on a credit card.

Is the car driveable for a while, or is this a dire situation? (I have kids to keep safe as well.) The earliest I could have it looked at is Wednesday, as I have very important things to do Thurs, Fri, Sunday, and Tuesday.

Is it most likely a timing chain issue? Would it be best to just replace the whole engine? How would I go about that? Do I have other options first? It makes it harder that I'm brand new to this town and don't know any mechanics aside from yelp reviews.

I'm kinda freakin out here. Any help would be greatly appreciated. Thanks!

Update: took the Explorer out for another errand today and there was no rattle under the hood.

 

[03WIExplorerLtd]

I suggest you get it looked at by a professional.

2004 have improved timing chains vs, lets say, a 2001. This is one thing in your favor.
Sometimes exhaust leaks can make ticking noises (and hissing as well). When your engine is cold, and the metal is not expanded, it could leak. You can't notice it when its warm because the seal is better.... Just an idea....

Do you have a stethoscope? Maybe you can pinpoint the noise better with one.

Search youtube for timing chain explorer - its terrible sounding. I know my tinny computer speakers make it sound worse, but it still is awful.

I have a little one as well, and can appreciate safety being at the top of the list.

Good luck and let us know.

 

[Tranquillity]

Thanks so much for the reply!

I searched youtube for the timing chain videos. The sound my Explorer is/was making is definitely not that sound...I think I can start being a little relieved!

It hasn't made the noise since a few days ago, and it's only happened twice total now. Seems like I'll keep being aware of anything I hear and take it from there. Thanks again!

 

[Joscibo]

I suggest you get it looked at by a professional. 2004 have improved timing chains vs, lets say, a 2001. This is one thing in your favor. Sometimes exhaust leaks can make ticking noises (and hissing as well). When your engine is cold, and the metal is not expanded, it could leak. You can't notice it when its warm because the seal is better.... Just an idea.... Do you have a stethoscope? Maybe you can pinpoint the noise better with one. Search youtube for timing chain explorer - its terrible sounding. I know my tinny computer speakers make it sound worse, but it still is awful. I have a little one as well, and can appreciate safety being at the top of the list. Good luck and let us know.

Not sure the 04's are any better than an 01. I recently have purchases 2 04's to put engines in to drive. Both had bad timing chains and bent valves etc.... Rattle is the beginning of the end in my eyes. I would shop for a good used engine before I would pull it to fix the problem. Labor is a killer if you can't do it yourself.

 

[DrkPony]

It could also be serpentine belt tensioner, my 04 was squeaking when cold. After the belt and tensioner replacement it's quiet, This is a inexpensive fix if it's the cause of your noise.

 

[cross6]

A loose spark plug(s) will sound like that and hiss at the same time.

"it was serviced: spark plugs and wires were replaced"

Hmm yep, there ya go.