ticking noise underneath the car

[hanatsuki]

im not sure if it does it when im driving, but when im in neutral or after i turn off the car there's this ticking noise right underneath the car, it sorta sounds water dripping on tin foil. I know when i have the ac on water just spews out from underneath but i dont have it on. anybody? if you guys would mind using lamest terms with me since I dont know much about cars.

[StockSolara]

Are you sure it isn't from the engine bay? because that dripping noise is normal from the engine bay. . . it's just oil dripping back down the block

[SpeedSTARs]

SUP Bro,

Like StockSolara says.

The dripping on tin foil sound is just the hot engine oil dripping on the oil pan. It is more present when the car is new or when the engine has been running for awhile on long trips. Usually this is the early stages of the break-in period. This is when the metals are in the heat treating stage of the break-in period. It is in a stage where the material picks up some martinsite (a hardening process where iron is more present in the micro structure of the metal). This is a good thing. It allows the metal to take more stress (Such as shock/ vibrations, bending and hardness). In laymen terms, the metal gets stronger from the heat treatment.

Now the dripping of liquid or water on the ground is from condensation build up. This condensation is from the AC coils. It will always be present as long as the compressor (AC is turned on) is running. This is normal.

[hanatsuki]

KooL thanks guys

[Jon11582]

SUP Bro,

Like StockSolara says.

The dripping on tin foil sound is just the hot engine oil dripping on the oil pan. It is more present when the car is new or when the engine has been running for awhile on long trips. Usually this is the early stages of the break-in period. This is when the metals are in the heat treating stage of the break-in period. It is in a stage where the material picks up some martinsite (a hardening process where iron is more present in the micro structure of the metal). This is a good thing. It allows the metal to take more stress (Such as shock/ vibrations, bending and hardness). In laymen terms, the metal gets stronger from the heat treatment.

Now the dripping of liquid or water on the ground is from condensation build up. This condensation is from the AC coils. It will always be present as long as the compressor (AC is turned on) is running. This is normal.

Thanks for the explaination. I was always wondering what that was. My friends new Chevy did that, and I thought it did that because it was a Chevy because mine didnt. Now I know all new cars do that.

[DatSRBoi]

SUP Bro,

Like StockSolara says.

The dripping on tin foil sound is just the hot engine oil dripping on the oil pan. It is more present when the car is new or when the engine has been running for awhile on long trips. Usually this is the early stages of the break-in period. This is when the metals are in the heat treating stage of the break-in period. It is in a stage where the material picks up some martinsite (a hardening process where iron is more present in the micro structure of the metal). This is a good thing. It allows the metal to take more stress (Such as shock/ vibrations, bending and hardness). In laymen terms, the metal gets stronger from the heat treatment.

Now the dripping of liquid or water on the ground is from condensation build up. This condensation is from the AC coils. It will always be present as long as the compressor (AC is turned on) is running. This is normal.

Dam..Science guy.. Thats what Im going to call you now.. Thats some high tech stuff there.. Awesome.

[Solorange]

All cars tick like that after you shut them off. And yes its precisely what speedstar said.

[Hefty]

Okay I specifically listened for where the sound is coming from after reading this thread. On my 1999 Solara it makes this sounds pretty loud and with a fast tempo and comes straight from my muffler.

The explanation of the oil draining back into the sump sounds good but I really don't think thats what is happening. First of all the one thing that sticks out in my mind that would discredit the dripping oil into the pan theory is that there should be a windage tray in the sump area that scavages oil from the crankcase back into the oil pan. This would prevent oil from dripping onto the pan itself. The oil returning from the engine would pour down straight back into the reservoir of oil sitting in the bottom of the pan. In other words there wouldn't be tiny drops of oil bouncing and skirt across a hot pan surface. I imagine what you are trying to describe is the sound of oil hitting a hot metal surface making a popping cracking sound much like pouring cooking oil on a piping hot skillet while cooking.

No, I believe the sound eminates directly from the muffler on my car. This noise is the sound of metal contracting back into its original shape while it cools down. This sound happens on some cars versus others because of difference in the tolerances between the exhaust pipe flanges. Either tightening or loosening the flange bolts would change or eliminate the sound. Usually when I take car to have exhaust work done the guys at my muffler shop will apply Red Hi-temp RTV to the inner surfaces of the exhuast pipe flanges to make a better seat and seal between the surfaces. Perhaps this might help if it really got on your nerves. On my Honda Civic I hear this noise came straight from the exhaust manifold. On Honda 4cylinders they have a large manifold heat shroud that make all manner of noises as it goes through thermal expansion/contraction.

[bassthrive]

the ticking is from metal expansion and contraction due to heat from the engine.

[SpeedSTARs]

Okay I specifically listened for where the sound is coming from after reading this thread. On my 1999 Solara it makes this sounds pretty loud and with a fast tempo and comes straight from my muffler.

The explanation of the oil draining back into the sump sounds good but I really don't think thats what is happening. First of all the one thing that sticks out in my mind that would discredit the dripping oil into the pan theory is that there should be a windage tray in the sump area that scavages oil from the crankcase back into the oil pan. This would prevent oil from dripping onto the pan itself. The oil returning from the engine would pour down straight back into the reservoir of oil sitting in the bottom of the pan. In other words there wouldn't be tiny drops of oil bouncing and skirt across a hot pan surface. I imagine what you are trying to describe is the sound of oil hitting a hot metal surface making a popping cracking sound much like pouring cooking oil on a piping hot skillet while cooking.

No, I believe the sound eminates directly from the muffler on my car. This noise is the sound of metal contracting back into its original shape while it cools down. This sound happens on some cars versus others because of difference in the tolerances between the exhaust pipe flanges. Either tightening or loosening the flange bolts would change or eliminate the sound. Usually when I take car to have exhaust work done the guys at my muffler shop will apply Red Hi-temp RTV to the inner surfaces of the exhuast pipe flanges to make a better seat and seal between the surfaces. Perhaps this might help if it really got on your nerves. On my Honda Civic I hear this noise came straight from the exhaust manifold. On Honda 4cylinders they have a large manifold heat shroud that make all manner of noises as it goes through thermal expansion/contraction.

Yup… The windage tray prevents the oil from being sucked straight out of the pan to retain the oil in the sump region. The reason the oil is being sucked out is because the crank shaft creates a turbulence that basically vacuums out the oil. That is why the windage pan/tray was designed to eliminate this problem. This windage tray could be the ticking metal sound your hearing. This is where the oil is dripping on the tray and then back into the pan. Since the windage tray is a thin 16-18 gauge steel, it will have that tin foil sound when oil drips on it. The darn things like a turkey pan.

Option two if the sound is coming from the exhaust system or the exhaust manifold, heat shield (on the manifold). It really depends on the material and process (ceramic coating etc) used on the exhaust system. Stainless Steel parts are more prone to have this dimensional thermal instability of thermal expansion and contraction. That's why you don't or rarely see stainless steel catalytic converters because of its unstable tolerances after the fact that the material has grown so much out of spec.

[Hefty]

Everytime I've heard that ticking noise it comes from the catalytic convertor and muffler. What you have in those areas around the catalytic convertor and muffler are several different metal types at various gauges which expand and contract at different rates causing a shearing action and resultant audible noise.

[SPF 0]

I wonder if it might make sense to have a mechanic put it on the lift while it's idling. It should be fairly easy to track down the noise at that point.

[WTF??]

I wonder if it might make sense to have a mechanic put it on the lift while it's idling. It should be fairly easy to track down the noise at that point.

yeah stick your ear next to hot metal

[SPF 0]

yeah stick your ear next to hot metal

If he can hear it from the passenger compartment, IMHO, someone outside of the car should be able to hear it as well. If the noise needs to be further pinned down, a stethoscope should prevent any unsightly and painful singeing.

Please excuse me if you're just kidding.

[i3oostedcubes]

I know this is an old post but I have this problem. The ticking. I knew it sounded like metal contracting and expanding due to heat as most cars tick when they are shut off but mine does it while running too. Only audible outside underneath the car but thankfully not in the interior. Is there any fix for this? Different type of Muffler or a high flow converter?