Loud Fast Ticking/Clicking Noise, Started Yesterday
 

Need some assistance identifying this loud fast clicking/ticking noise (like a stop watch or cards you use to take to the rear spokes of your bike tires when you were a kid).

My guess is it's stemming from the upper manifold or some sort of switch/value, small exhaust leak? I do not think it's lifter noise, due to the change in click speed on revolutions and the fact it started making the sound overnight. I had slight come and go lifter noise in my old Jeep YJ and it was nothing like this.

I changed the oil last saturday (same as always, Mobile 1 high mileage synt 10w40), put new brake pads on and some headlight parking light bulbs. I noticed the valve cover rear passenger side bolt was wet and wet around the lip. I was going to tighten all 4 value cover bolts but they are not metric (8mm 12p), look to be some sort of 16 star torx male head bolt or something. :( I have not had a chance to hit the auto store yet to find a socket head. I do not think this is what is causing the sound though. Weird.

No codes flashed, no performance drop, engine feels and runs the same as always. Any suggestions? It's driving me crazy today! lol

[youtube]http://www.youtube.com/watch?v=8o0T2ne3f2A[/youtube]

While driving. You can hear the change in click speed per rev,

[youtube]http://www.youtube.com/watch?v=XgsgW9nVBHs[/youtube]

The problem with videos/recorded audio is that its so difficult to tell what the real tone and relative volume of a sound is.

What you ought to do is get a mechanic's stethoscope (or use a long screwdriver and put your ear up to the handle) and see if you can locate the sound. Is it louder on one valve cover than the other? How about in a particular part of the cover?

I'm just guessing as to the area, but you get the idea. Just try to narrow it down more if you can, and the issue will either become evident or at least you'll have more information to post.

As it stands, since it goes with the RPMs, it could absolutely be anything from a collapsed lifter to a broken valve spring. If it's as loud as it appears to be, I wouldn't want to drive it until I sorted it out.

I will see if I can find something to listen when I am shopping for the torx sockets at the auto store today to tighten the valve cover.

With a scope, what am I listening for on each valve cover exactly? Should I go ahead and stock up on some oil if I need to take the value cover off? I have never removed the cover before. Do I need to drain any oil beforehand etc?

And thanks Daryl for the help.

I'm not suggesting you take the valve covers off at this point, but if you do, change your oil. No, you won't lose any taking the covers off, but you want to make sure you don't leave crud in the system. Unless you're sure you didn't get any in there with the covers off.

I'm suggesting you leave everything together and listen for exactly the noise you are hearing. You are only using the steth or screwdriver to determine where it is the loudest, which ought to be the source (or near it). If the happens to be under a valve cover, note about WHERE along the cover (so you know what area to look in), pop it off, and have a look.

Gotcha. Trying to pin point the loudest sound mark. Sounds like a plan.

The bolts holding the valve cover look weird. I read 8mm 12 point. I tried 8mm 6 point (that's all I had) and it did not fit. The bolts looks like a weird star pattern or something.

I am gonna buy an 8mm 12 today and try that I guess. Heck that's all the store has. I at least want to tighten the bolts.

6 point will not work you definitely need 12 point because of the bolt pattern.

Yes...a 12 point will be just what you need.

Also, get your hands on an upper to lower intake manifold gasket, since I'm assuming you'll be pulling the plenum off to do this.

Mike is going to call me. It could be a bad/clogged purge valve. Man I hope so.

I am still planning on getting the stethascope and having a good listen tonight. That and the 8mm 12 pt. :D