My '96 has some strange problem. -Occasionally- when I start it up, i get this clicking noise... sounds as if it's coming from the motor. The best way i can describe it is as a rotating SOMETHING that just clicks really loud at times... but usually about 30 seconds later it will stop, or become much quieter. A lot of the part's in it are brand new to an extent, my oil is good.. so i know it's not that. Any idea's will be greatly appreciated.

I signed up just to answer your question...
I just discovered the cause of this noise on my father's 99 blazer last night. It's the rear driveshaft universal joint.

If you raise the car up at the back and slide under, you can twist the driveshaft back and forth and you will hear the clicking noise coming from the rear universal joint right where the main driveshaft connects to the rear differential. I believe the whole driveshaft needs to be replaced.

Jason

I can't tell you what it is..but I really don't think it's the driveshaft in this particular case.

Are you driving or in park when it happens?

Do you get the sound when the engine is cold only?

That happened to me a couple of months ago. I had a sparkplug mis-firing. I fixed that and added some EOS and it is working great now.

Yes, it only happens when the engine is cold (it usually stops after 30seconds to a minute). But it also doesn't happen each time I start up the car... maybe half the time or a little less often, but I just don't want it to become a big problem.

It happens in both park and drive and clicking actually speeds up as I speed up.

Klam: The clicking is from the front of the car, not the back.

That's the same way it was with mine. Except it would last a lot longer sometimes.

Now that i've played around with it a little more, i've discovered some more details about the problem (still havent gotten around to calling a family member who is a mechanic). I noticed that it stops when the car is all warmed up from moving, not just warming up idle... but moving.

I found this out by warming up my car in park for about 15 minutes, then reving the engine in park, the clicking noise disappeared for a while after that. Now that I have anti-freeze/coolant back in my car the clicking noise stays longer because obviously the engine wont heat up as fast. Pretty much now it stops after 10 minutes of driving, but still doesn't sound healthy at all. More thoughts on the possible problem would be helpful.