2007 Yaris 1.3 strange noise

[Sipart]

Hi. Comments and advice welcome. Collection of clips in this YouTube video of noise when pulling off a driveway. 
https://youtu.be/5MLZbbC6m6E
The noise is mainly present when in low gears and under load. 
When stationery and revved then it's normal. 
Otherwise it drives and performs well.
It's been to a local garage twice but they haven't been able to resolve it. The last time it went they tightened the inlet manifold bolts and it was OK for a week but the noise returned. Trying to avoid a return visit and paying more money out if this is something known about that I can resolve.
Cheers in advance.

 

[flash22]

That odd, does the engine lack power at the top end ? Does it do it if you give it a bit more gas when bringing up the clutch ?  Remove the aux/fan Belt and see if it still does it

What's the service history like ? What's the mileage ??

[bathtub tom]

Sounds like an exhaust leak to me. Have you tried blocking the tailpipe and listening?

Edited June 7, 2021 by bathtub tom
Further thought.

[Sipart]

Hi flash22. Thanks for the feedback. 

Power at top end is fine. If you over-rev it when bringing up the clutch then yes noise can be mitigated to a degree. It is worse if you labour it lower down the rev range.

Aux/fan belt as in the alternator ribbed belt around various other pulleys (serpentine belt?)? The car has AC. Can I run and do some basic up and down runs on a short drive with the belt off?

It's serviced every year and it's done 85000 miles. It's been to a local garage (reputable and been in the town for decades) a couple of times for this noise (and services/MOTs done there as well). So you would assume they would of tried this?

Cheers

[Sipart]

Hi bathtub tom. I will try to try that but it only makes this noise when moving and in gear - so maybe a bit difficult. But previous work dealing with this issue did end up with a new cat and mid box (they said exhaust was breaking up inside).

I am a bit concerned we may have paid for work we didn't really need. I appreciate the engineers need to take time to investigate and sometimes it's trial and error and that time costs money. But the bill for cat and mid box for approx £380 was one bill. Some of that may have been necessary of course. And then further investigation and manifold tightening work was £80 (couple of hours labour+vat).

 

[bathtub tom]

If you get someone to block the tailpipe at tickover (I used to put the sole of my shoe over it) and listen around the engine bay, you'll definitely hear if it's an exhaust leak.

[flash22]

It may be a slight miss under load - Pull the spark plugs and check the gaps, if it's on the original plugs they are about due a change, i wonder if you have oil down the plug holes

[sproutdreamer]

My 2003 1.3 auto has a similar sounding noise only when pulling away. This only appeared after I had a new exhaust fitted. I think it is to do with the exhaust flange bolts and tension springs but I have done trying to fix it and I now live with it.

I will be interested when you fix it to find out what it was.

[Sipart]

Thanks for all the responses. Will try some of these things and report back (or if I run out of patience what another garage does!).

The Aux/fan belt around the alternator and various other pulleys (serpentine belt? the car has AC) - can I run and do some basic up and down runs on a short drive with the belt off?

We did notice today it made this noise a lot less/hardly at all when put and about and only difference was the constant use of the AC.

Cheers

[flash22]

as long as it doesn't get hot also check the idlers for slop or rumble

[Sipart]

Sorry long time not replying with the solution. Went to a different local garage and they correctly diagnosed the serpentine belt as some suggested above. A relatively cheap and easy job. Thanks to all for responses.