vz sv6 sounds like tractor, vibrates in idle..

[kicker12]

Hi all, this problem has been going on for a while now but since I've finally booked it in to get it checked out i've become more and more curious. I've searched everywhere on these forums, the internet, google, and nothing.

When i turn my car on, it's fine....sounds and runs like normal, then after the engine warms up a bit and the revs drop (eg when im pulling up at a set of lights) often the engine will start to sound like tractor and the noise fluctuates sometimes going louder then softer...it's a pretty bad sound.
In addition to this, often while idle and making the noise the engine will shudder and you can definitely feel it form within the car.

However as soon as you rev the engine a bit the noise and shuddering completely goes away as if nothing was ever wrong, and on the rare occasion when i rev it at the lights and the revs drop back to idle the noise stops even in idle.....but then if i rev it again and drop the revs back to idle after the whole problem comes back.

I've been searching around the internet and thought it might be an engine mount, something might be loose on the engine causing the noise, something may be blocked like an air valve or i don't really know.

And yesterday for the first time my car just cut out at the lights, after taking it for a short drive (i've only been driving it on short runs over the last few months maybe like 1 every week or two just to keep everything ticking over).

So anyway i've booked it in at the mechanic but thats for 2 weeks time and was wondering if anyone here possibly has an idea of what it could be....

Cheers guys

 

[bigdaddycool]

Pot guess here.... but i heard the vz sv6's have an issue with their powerchain cause of the variable exhaust camshafts (often rattle and carry on)...... maybe it'll have something to do with that.

but yeh take it to someone, see what they say.

 

[STRIKE]

Wheres the sound coming from? It sounds like you have a heat shield loose thats rattling away.

 

[neet_wagon]

.....................I know nothing apparently

 

[kicker12]

thanks for the responses guys, i know i shouldn't be driving it, it's been off the road for about 2-3 months now just saving to get it fixed and doing a few things to the interior i've wanted to do for a while. i've driven it probably maximum 30km in the last 3 months.

haven't really managed to find much on the timing belt issue...i'll post up a video of the noise soon and see if anyones heard it before

 

[andyman]

considering the alloytec dosnt have a timing belt id rule that out, there was a few isolated makes that had a defective timing chain that strectched, if it was the chain it would rattle all the time,

if its making the car shuddder as rattle wont do that, id suspect a coil breaking down causing and ignition fault

 

[Corbs1234]

i did have this after my first service on my ute. the mechanic didnt properly re-attach the spark plug leads. it'd idle like it had a cam for a bit, then the revs would increase as if the aircon had been switched on. then it would go back to a lumpy idle.
but the stalling at the lights is strange...
is it a metallic sound when vibrating though?

 

[impulsive]

considering the alloytec dosnt have a timing belt id rule that out, there was a few isolated makes that had a defective timing chain that strectched, if it was the chain it would rattle all the time,

if its making the car shuddder as rattle wont do that, id suspect a coil breaking down causing and ignition fault

maybe this has caused the bolt to come loose on my cam, causing the current problem. Do you think?

 

[andyman]

maybe this has caused the bolt to come loose on my cam, causing the current problem. Do you think?

nup youd have a cam out of round, tunnel misalignment, or unlucky enough to have a dodgy head casting

 

[kicker12]

Ok so i've uploaded a soundclip of the noise onto youtube.

You can hear me fiddling around withe the camera first....then you can hear me get out my keys and turn the car on and it idles...and then i rev it a little bit (engine was warm when i did this a little while ago..took me ages how to work youtube lol) and you can hear the engine drop back to idle and make the tractor sound, its usually not as consistent as that though, like it'll get louder and softer and the engine shudders harder and softer etc. but that only ever happened while i was driving it and i'm not going to go do that anytime soon, but you get the idea.

Anyway, then after the tractor noise you can hear me rev the engine again and it sounds normal while i rev, and sounds normal when it drops back to idle. but if i had revved it again a bit when it drops back to idle it would've made the tractor noise again. Confused yet? lol.
thanks for the responses guys started to get really worried about this now..

YouTube - idle noise.mov