I should have mentioned it, but yes it is 4x4.

It seems to me that the sound is coming from directly behind the speedometer. It could possibly be an ignition issue because thats the general area of the sound. But, I've never had any issues with starting up or running in accessory.

It does have an aftermarket CD player. I plan on putting in my stereo and speakers from my old truck so I will take a look at that wiring when I pull the radio out. Im not so sure about that though, because the sound isn't coming from the speakers at all (at least, not that I can tell).

 

When i said ignition, i didnt mean the ignition switch, but the actual ignition system. IE; plugs, wires, coils.
The ignition system due to its inherant spark nature produces alot of RF (radio frequency) emissions.

But as you noted it seems to be comming from the gauge cluster my thought probably no longer applies.

 

Sounds like the speedo cable from what ur describing. Disconnect it from the trans. and drive again, see if it stops. Probably need new cable. It may set a code after, but you can clear it.

 

You may also notice the speedometer needle bouncing a little as you drive.

 

There is no speedometer cable -- it's all electric. The noise COULD be coming from the speedometer mechanism somehow, but it wouldn't be because of a cable.

The EVAP solenoid should be mounted towards the rear of the driver side valve cover -- which would place it very close to behind the speedometer area. Easy check -- simply unplug the solenoid and go drive. It'll throw a code (probably a P0443), but at least you'll know that that's what was making the sound (or not).

 

Also check all the firewall body grommets. The previous owner may have drilled a hole or opened up a grommet and forgot to replace it, if he was running power wires or something to the stereo. You never know... The noise could be an exhaust tick that comes in through an open hole in the firewall.

Did you say it was based on vehicle speed or engine speed? If you're driving along at 25 MPH or so, and slip the transmission into neutral and let the engine idle as you roll down the road, does the noise change?

 

I'm 99% sure its vehicle speed but dependent on how much Im pushing in the gas. Like I said before, its still only on acceleration and cruising at a constant speed. If I take my foot off the gas, it doesn't tick.

I did notice that the first time I start up and go driving, the ticking doesn't start until I hit about 35 or so. Then it continues to tick when I give it some gas. Sometimes the tick goes away as Im driving, and other times it continues to tick.

An exhaust tick isn't out of the question... I did notice the manifolds are extremely rusty and it wouldn't be surprising if there was a hole. But under these circumstances I find it hard to believe that that would be the issue.

 

If it were an exhaust tick, it'd more than likely be because of pitting at the manifold-to-block interface. I don't believe these engines use exhaust manifoldgaskets, but if they do, that could be the culprit. There may also be a donut gasket that's bad at the base of the exhaust manifold. Could also be a broken exhaustmanifold bolt, allowing the manifold to separate slightly from the block. Lots of possibilities, but it sounds like it may be an exhaust tick. That would absolutely manifest itself more as the throttle increases -- and probably go away as you get off the gas.

 

an exhaust leak is possible i guess. depending on the severity of the leak, you could pretty easily hear it under the hood, and even stick your head all around to narrow down where it was coming from. ive had exhaust leaks in cars before and they areusually pretty easy to find. they also seem to be louder at lower rpm's and go away the faster you go, or when there isnt a load on the engine, unless its a real bad leak, then they just get louder, and in that case youd definatly hear it with the hood open.

 

i'm pretty sure its the evap solenoid thats the same exact thing mine does and i could barely hear it if at all when i had the hood up looking for it...if you hold the thing when its running then give it a little throttle either on the tb or have someone rev it you should feel it pulsate faster. like i said i can hear it plain as day inside but barely if at all under the hood which means its most likely not an exhaust leak cuz i'd be able to hear it more with the hood up. try that if you can barely hear it with the hood up it shouldnt' be an exhaust leak.