clicking coming from center console on 72 240z

[patEOD92]

whenever my car is running there is a loud clicking sound coming from the bottom the the center console. it seems to quiet down a good bit once i have the car driving but it is extremely loud while idling. does anyone have any suggestions on what it could be?

[Captain_Zeros]

Check out your driveshaft U-joints.

[zKars]

If it happens while the car is sitting still, its an exhaust leak. If only while moving, its what Cappy says.

[siteunseen]

Does it go away when you push in the clutch pedal while idling?

[patEOD92]

No, its more of a mechanical clicking. Like someone is clicking a pen through a microphone.

[patEOD92]

i cant figure out what it could be because it comes from the center console and you cant hear it when your out of the car.

[zKars]

I think we have now established the car does not have to be moving, so its not the drive shaft u-joints.

So we are down to an exhaust leak or something in the transmission perhaps.

Ok, answer this question. If you are sitting in the car at idle, and you hear the sound, then you increase the RPM's slowly up to say, 2500 then back down to idle (do not move the car, only touch the gas pedal), does the clicking rate (clicks per second) increase and decrease at exactly the same rate as engine RPM?

I have another an idea, remove the console and the boot around the shifter hole in the transmission tunnel so you can see and/or hear the noise source more clearly.

[patEOD92]

the sound stays pretty constant untill the car is actually moving, then it gets quieter. And i think theres confusion about what i mean by center console and thats my fault, its not the center console but more around the bottom of the instrument panel

[grannyknot]

Is the fan on, something caught in the squirel cage?

[Mikes Z car]

If I am interpreting this thread correctly my car also sometimes clicks. It is a steady rhythmic click about one or two clicks per second on my car and doesn't seem to be related to RPM or whether the car is moving. With the great ideas here I will be in a better position to analyze it if it does it again. I initially interpreted it as a thermal click but that made no sense to me. I thought it was coming from the starter area or passenger footwell area.

Edited April 1, 2014 by Mikes Z car

[siteunseen]

Wouldn't the bottom of the instrument panel be where the transmission bolts up to the engine? Climb under there and tighten some bolts maybe?

[Mark Maras]

I believe it's time to break out the 3' garden hose stethescope. You'll be able to listen down in the tunnel & find out if the noise is coming from the outside before removing your console. I'm still unsure if the noise changes with the clutch pedal in.