Cyclic clicking noise: front axel or what?

[Brian]

So I'm getting this clicking or tapping sound coming from the front of the car, probably the passenger side. It's cyclic and starts out slow when I'm starting from a stop, and by the time I reach 20 MPH it's fast and steady: click-click-click-click... (It remains as I go faster and is pretty loud.) But when I take my foot off the gas, it goes away. The only time I hear it when not giving it gas is when the car is very slow when coming to a stop, and of course it is a slow noise then. Does this indicate the half shaft axel on that side has gone bad? If not, what is it?

[dannmarr]

Could be a cracked flex plate.

[Brian]

That had occurred to me, but the sound does seem tied to wheel speed...and there's nothing while idling or when the car's moving at speed without giving it gas. Does that make a difference?

[fasteract7]

Might be the inner passenger side CV..symptoms more like this side of half axle than the outer CV. Jack the car up and manually spin that rim. Grab the half axle and push it in and out and see if it clicks or has excessive play. If nothing, jack up front, block rear tires, parking brake secure,pull FWD fuse and gently accelerate front wheels to listen for your noise.

[gearheadE30]

OP, your diagnosis is right on the money. The reason the noise comes back at very low speeds is because as you approach a stop, the brakes and engine start to fight each other. It is this characteristic that results in the car creeping forward when you lift your foot off the brake. If you were to put the car into neutral before coming to a stop, my guess is that the noise would disappear. CVs tend to click when they dry out and wear over time, as the balls that transfer power will wear grooves and elongate the slots they ride in. Generally the problem is created or exacerbated by a torn boot, either on the inner or the outer CV.

[Brian]

Thanks, guys! Yes, when breaking in neutral it does go away. It will be a few days until my new part arrives. The sound became worse on my way home today. I still have to get to work on the day after tomorrow. Is it safe to drive on?