Strange clicking only during acceleration, 98 Trans am

Hello everyone, need help diagnosing a mysterious clicking iv been hearing. I got an a4 Trans am, a little over 100k miles. I only hear it during driving, only when accelerating from a stop. Once it gets to 25mph it pretty much stops. This clicking happens randomly, some days no clicking. Engine inspection looks fine, no coolant leaks, changed oil yesterday and oil looked normal. Transmission fluid fine, the a4 shifts perfectly. No check engine light either. I hear the clicking when the engine is hot or cold. Sound appears to be coming from the engine. Clicks will stop as soon as I let go of the gas. Here's a video of the sound, any help would be much appreciated. Thanks

https://www.youtube.com/watch?v=AnSJ...e_gdata_player

almost sounds like a heat shield is loose.


hard to say. Do you hear this when at idle? or only when you move?


Does it sound like it's coming from under the center consul?

At idle there's no clicks, just when I'm giving it gas..once the RPMs are steady the sound goes away..

No the sound definitely is coming from under the hood.

In doesn't make this sound all the time. Yesterday it was perfect and today driving to work the clicks returned. Also my car is mostly stock, just a k&n fipk kit and Shorty headers. Oh and loudmouth 2 exhaust.

Did the car make the noises before the mods, or after?

The mods were done years ago.
I still can't figure it out, I did notice a missing gasket on one of the air pipes connected to the headers, I replaced it but still heard the clicks.

possible spark plug wire broken and arching to the headers... could also be a lifter starting to go or a rocker arm crapping out...

I replaced the spark plugs, and the wires looked clean. I have some msd 8.5 wires. I guess it could be the lifter/rocker arm giving out but wouldn't there be any difference in performance or maybe shaking? The car runs great, just an annoying ass clickon random days.

Sounds like an exhaust manifold gasket leak to me.

SteveC :(

yeah it could be, i did check the around the headers to check for any stains and didnt see anything. I probably need to check underneath to see if there's any exhaust leaks.

how did you check around the headers??? use soap and water mix to see if it bubbles if you didn't do that...

x2 exhaust manifold gasket.

I would also try to find/make a stethoscope. pull the E-brake and have someone put it under a load while you poke around under the hood listening to everything. even with just a long screwdriver cupped to your ear you can hear all kinds of shit you never heard.

The car actually has to be in motion for the clicks to happen unfortunately making it hard to really see where in the engine its coming from. However I did want to share something interesting I found out. The clicks were gone for about 5 days and then returned today. I noticed if I turn off the car, and restart it, the clicks went away. So the process happens during start up, and I have a 50/50 chance of getting that sound. Plus, if the car starts fine, the clicks will never come up as long as the car is on and and vice-versa.

I'm going with:

A-exhaust leak
B-if it's moion related, wheel weight scrubbing on a front strut
C-brake pad chatter

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Hopefully the cause isn't internal.

My car is doing the exact same thing. Any solution ever found?

Welcome to the site, Elias. :)

Looks like the OP never posted back up on this one. Can you determine about where your sound is emanating from? Exhaust leaks, heat shields, loose brake components (happens more than you would think) and loose suspension components (especially the front torque arm mount) are always the initial suspects.

Quote:

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Originally Posted by pajeff02

Welcome to the site, Elias. :)

Looks like the OP never posted back up on this one. Can you determine about where your sound is emanating from? Exhaust leaks, heat shields, loose brake components (happens more than you would think) and loose suspension components (especially the front torque arm mount) are always the initial suspects.

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Thanks for the reply Jeff! As far as isolating where the sound is coming from; I haven't been able to yet. It's difficult because the noise only happens when I'm actually driving and not at idle. But I'll be sure to check out the suggestions you made. Thanks again

Good luck. Sometimes helps to have a passenger who can move around a bit to try and isolate the noise rather than having to focus on driving. Let us know what you find.

i had a car with a cold air intake on it that made a loud ticking on acceleration , especially under a load . lt turned out to be the egr valve opening and carrying the sound back out through the cold air intake . Just a thought .

^^ Interesting. The problem is on an '02 though which is not equipped with an EGR system.