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Clicking noise when foot's on gas

My 2000 Bonneville makes a clicking/light grinding noise when I rev the engine, both when the car’s in motion or in neutral, only when I press the gas pedal.

That is a mighty vague description. Open the hood and have someone rev the engine while you try to identify the location of the source of the noise. See if you can get a clearer description of what it sounds like.

sounds vaguely electrical, coming from under engine block or near/under serpentine belt/pasenger side no sparks visible, actually seems louder inside car than when you stand outside with hood up, it is winter haven’t been running ac, but have not run it without defroster to see if noise persists, no warning lights, car runs fine otherwise, temp gauge also fine

Barn Dog, To Me There Is A Difference Between Clicking And Light Grinding.

Did you try it without defrosters? Does the noise change with engine temperature? Is it quieter or louder when the engine is cold or warmed-up? It goes away completely at idle, in park?

Since we can’t hear the noise, the description is critical. Can you relate the sound to something everbody is familiar with, like clicking fingernails on a hard surface or marbles rolling around in the bottom of a coffee can, or whatever would come closest? Does the sound change with a chnage in heater blower speeds?

You can sometimes use an automotive stethoscope to find unwanted sounds. They really isolate and amplify the sound in stereo (both ears). Touch (sometimes press on) different components (none that move, you’ll deafen yourself) and you may find your noise. Last time I was at Sears they had a Craftsman for under 20 bucks. Should it not work on this particular sound, you will still have a valuable tool to last you a lifetime. Some people just use a length of hose as a stethoscope (not stereo, low budget, really tacky). I prefer the professional “Dr. Motors” look.

Mine (not a Craftsman, but elcheapo) just diagnosed a bad air conditioner tensioner pulley that made a sound possibly similar to what you are describing, but mine was louder under the hood, at idle, engine cold. I lightly pressed the nut holding the spinning pulley and heard a grinding roar (beyond the normal sound). I removed the belt to verify that the sound stopped when the engine ran. Be careful where you put that probe when parts are flying around in the engine compartment and make sure no loose clothing or hair gets away from you and remember, some things get quite hot. Sample some different places on the block, heads, accessories run by the belt(s), etcetera. A little practice and you’ll know normal sounds from something sinister.

A side benefit, using your new tool out in the driveway is a good way to get the neighbors gossiping. I always enjoy that aspect, as I have a few who don’t mind their own business. You may even choose to listen to a tree or two, the garage, and maybe the dog. My neighbors wouldn’t even think of asking what I was doing.

Re: How I mess with my neighbors by using a stethoscope on inanimate objects. Very funny stuff, CSA. Reminds me, back in the day, we looked slightly askance when encountering someone walking down the street talking to themselves. Now, we know better: ear piece and cell phone.

Noise is tough to describe, sounds almost like a coffee pot pushing out the last few drops of brew cycle only a little higher pitched, like a high-pitched gurgling/spraying noise like you hear when you put your thumb over the end of a garden hose… only happens when I step on the gas, in motion and in neutral or park the driveway, my initial descriptions weren’t vivid enough or really on the mark. Yes, noise goes away when idling or in gear, anytime foot’s not on gas pedal. Noise is there whether defroster/ac is on or off.