Squeaking / creaking metallic noise
Dear group members,
I’m posting here out of pure desperation because neither I nor my mechanic have been able to figure this problem out for months.
About a year ago I bought a 2008 Toyota Yaris 1.3 petrol (XP9F). Unfortunately, the previous owner neglected the car quite badly, so there were a lot of things that needed fixing. Thankfully, over the past year my mechanic and I managed to sort out most of them.
However, toward the end of winter a new and incredibly annoying problem appeared:
Whenever the drivetrain is under load, during forward/backward weight transfer, when the engine applies torque and the car “tightens up” / starts moving, something makes an extremely loud squeaking / creaking metallic noise.
The source of the sound is almost impossible to locate.
The noise does NOT happen during vertical movement (up/down) or side-to-side body movement. It happens specifically during load transfer, especially when shifting in 1st, 2nd, and 3rd gear.
The gearbox and clutch are completely new, and the noise can also be reproduced WITHOUT using the clutch for example by rocking the car back and forth on engine braking.
We inspected the engine/transmission mounts, sprayed suspected contact points with copper grease spray, but the noise remained unchanged.
The exhaust gaskets and connections after the catalytic converter are new, solid, and secure as well.
What makes this even stranger:
With the handbrake engaged, in 1st gear, the noise can be reproduced while gently rocking the drivetrain at low RPM just enough for the engine/block to move slightly. HOWEVER, if the engine is turned off and we manually shake/move the engine by hand, the noise does not appear at all. That’s the part that completely confuses us.
We also checked the suspension, control arms, sway bar links, etc., and there are no signs suggesting the noise comes from there.
We can’t even determine which side it comes from — only that something is squeaking/creaking horribly loudly.
Has anyone here ever experienced something similar?
Any ideas where this could come from or what could cause it?
At this point we’re completely stuck. Every guess and every inspection so far has led nowhere.