Loud ticking sound on cold start up - Toyota Nation Forum : Toyota Car and Truck Forums

zettahertz · 04-23-2007, 01:10 AM

There's some loud ticking sound/vibrating sound on a cold start up coming from the serpentine belt/pulley area that just started 2 days ago after a 3 hr drive (some hard driving involved), but disappears after warming up and it's never had this sound b4. What can it be? Loose belt? or something more serious?

O yeah... forgot the important part. There's only that sound when it is put on Reverse/Drive gear and braked. So it sounds fine when it's on Park or Neutral.

marc780 · 04-23-2007, 01:46 PM

If the ticking is only coming from the belt and not the engine itself? Carefully check your belts, some of the ribs may be cracked or broken off the inside portion.
Spray some silicone spray on the belts, one at a time, then start the engine when its cold and listen. Noise gone? Replace belt. Noise still there? Check other belts the same way.

If the tick is still there after this, maybe you just need to change your timing belt, or maybe it is the alternator or other acc.

zettahertz · 04-23-2007, 03:17 PM

hmm, something makes me think it's not the belt. 'cus I've changed the belt at 45K (now at 65) and all it made was a squeaking noise that never goes away even when the car is warmed up. And this sound only occurs when there's a load, and I don't hear it when i just put it to park/neutral and press the gas. It's very difficult to pinpoint exactly where the sound is coming from. Very strange...

marc780 · 04-24-2007, 01:03 AM

Another way to test to see if the noise is in fact from a belt, or a belt-driven accesory. Remove the belt, one belt at a time if you dont have a serpentine type belt. Then run the engine and listen again. (You can run the engine with no alternator belt for a minute or two and it wont hurt anything.) If the noise is unchanged with the belt off, maybe it is your timing belt making the noise?

Webb26 · 04-24-2007, 01:28 AM

Zettahertz....how loud is this ticking sound? Regardless, as little as i do know about this problem, my friend has a problem similar to your description. His highschool auto teacher, after a couple compression test, said that it couldn't have been a blown piston, worn rings or anything of the sort, and his teacher as well as some local mechanic said that it probablt was a lose piston pin or something like that. As soon as i can talk to him, i'll find out more of his problem and let you know

zettahertz · 04-24-2007, 03:38 AM

dang, loose piston pin, seems kinda serious. better not be caused by the pulley.

It's like some vibrating sound from the passenger side. The first time it was kinda loud, u can hear it if it's idling (set to R and braked) w/ windows down and probably like 10 ft away the first time it happened (was parked outside).

It seems like the car has to be TOTALLY cold to make that sound. I drove at like 12PM (parked in garage), minor sound, can barely tell it's there. Then 6 hrs later... turned it on again, no vibrating. It was much louder when I parked outside overnight.

This engine uses a timing chain i believe. How often do u have to replace that thing? I'd expect it to be longer than the timing belt, and 65K seems like a pretty short time.

zettahertz · 04-24-2007, 04:57 AM

man, looked up some of the "noises" that a messed up engine can make and this is what i found:

http://books.google.com/books?id=U4T...ENSQ#PPA198,M1

interesting book

quite interesting i'd say...

Piston Pin Knock: "originates in upper portion of the engine and most noticeable when engine is idling and when engine is hot". That's kinda contrary to the symptoms cus it seems to happen when it's cold... very cold.

Webb26 · 04-24-2007, 11:46 AM

I Was going to add...that my friends car that has the piston pin knock, mostly occurs when the engine ie warm. So maybe your problem could be different, or not as severe.