Corolla vvti - tappety chatter under acceleration

zurbfoundation

late last week noticed this sound, i describe it as a tappety chatter - have an audio clip below you might be able to steer me right on it



https://clyp.it/z2degiim
(hear it at about 4 and 9 seconds)


its a 2003 corolla 1.4 vvti - 2nd engine in it so no idea on the milage. so under acceleration you get the sound.


I had a previous vvti avensis that drank oil for fun and i would know its time for a top up when i could hear the timing chain rattle. so i first thought it could be oil related. checked oil, nothing in it really (oil light has flashed on previous occasions prompting top ups so i know its working). so gave it a litre and half. sound persisted however.


Any suggestions welcome.



thanks for looking

Interslice

Is there oil leaking down the sides of the engine?

A litre and a half is a serious drop of oil to be burning internally.

zurbfoundation

no leaks. but when those vvtis decide to burn it you can forget it.



i got a tip to check the on the oil filter for the vvti solenoid - will check that out as a starting point.

Interslice

zurbfoundation wrote: »

no leaks. but when those vvtis decide to burn it you can forget it.



i got a tip to check the on the oil filter for the vvti solenoid - will check that out as a starting point.

If i was to guess at the noise i would have said something to do with the vvti. I've heard similar noises from different variable intake cars over the years.

greasepalm

https://www.youtube.com/watch?v=Awn34EnZ_fg

zurbfoundation

thanks - actually saw that vid - my issue is under acceleration, under particular load - so i will start with exploring a potential vvti oil flow issue

Tea drinker

I had a weak belt tensioner, it actually sounded like the engine was fvcked. It happened if you revved the engine sometimes when accelerating.
You could always run the engine without an accessory belt for a few secs.

zurbfoundation

good shout. i was driving it yesterday thinking timing chain, chain tensioner (if it has one) - the rattle is only in it from about 2900 to 3500 revs. then its gone

CJhaughey

Some of those plastic manifolds had a problem with the inner part coming loose and rattling, they are a twinwall design to reduce intake noise.
A plasterboard screw in the right place usually sorted it.

zurbfoundation

saw that must check it out. this sound is very metallic sounding if you get me

greasepalm

Plastic manifold if gone would feel the noise coming through it if gone.

zurbfoundation

thanks, will check over weekend, hope its that simple :-)

greasepalm

i cant remember if that has electronic or wire cable for accelerator so you might need someone in car to bring revs up and when hitting the right rev noise will kick in and you will feel it then.

zurbfoundation

has a cable

greasepalm

Handy then you can rev it under the bonnet yourself.

Avns1s

zurbfoundation wrote: »

good shout. i was driving it yesterday thinking timing chain, chain tensioner (if it has one) - the rattle is only in it from about 2900 to 3500 revs. then its gone

Is there a heat shield over the exhaust manifold and has it become loose by any chance?

CJhaughey

Drop the sump and check the oil pickup, the 4zz has a design that can get blocked with debris and reduce oil flow a lot.
You can modify it by cutting away some of the metal to allow better flow.
https://www.youtube.com/watch?v=0QQJIrd39V4

zurbfoundation

Avns1s wrote: »

Is there a heat shield over the exhaust manifold and has it become loose by any chance?

have not noticed that, but can check thanks

zurbfoundation

CJhaughey wrote: »

Drop the sump and check the oil pickup, the 4zz has a design that can get blocked with debris and reduce oil flow a lot.
You can modify it by cutting away some of the metal to allow better flow.
https://www.youtube.com/watch?v=0QQJIrd39V4

sh1t just did an oil change would have been perfect opertunity for that, but will def check it out. thanks for the heads up

greasepalm

zurbfoundation wrote: »

sh1t just did an oil change would have been perfect opertunity for that, but will def check it out. thanks for the heads up

That usually happens when you get lazy and dont change oil and filter regularly.Oil cap off look in and seeing crud on cap would suggest not often enough.I can look into mine and its clean.

Czhornet

Is it sluggish in accelerating?
Sounds like the timing is out a bit, the auld lad had the same issue a while back and when the timing was adjusted it was back to normal again.

zurbfoundation

Czhornet wrote: »

Is it sluggish in accelerating?
Sounds like the timing is out a bit, the auld lad had the same issue a while back and when the timing was adjusted it was back to normal again.

she does not have that symptom - still driving grand to be honest.