Kind of sudden onset of knocking during engine start.

[zegarnek]

Hi,

I drive manual Yaris 2007 (km - 120K, second owner approx 20K Km).

Last two days I noticed strange knocking sound, from the front, just after the engine starts. Then all goes quiet and the engine runs smoothly. It does not happen every time at the start, and the noise varies in strength but usually it is one klang/knock. It could be bit on the left side (from driver's seat).

I am worried that something sudden and terrible will happen and I might kill the engine on the way to a mechanic.

Did anyone ever encountered anything like that?

Thanks

ps

I tried to record that noise but at this particular time it was very soft. Next recording tomorrow.

Edited September 25, 2015 by zegarnek

[trentmeyer23]

Does it sound similar to this?

[zegarnek]

Hi, Not at all like this, this continues for a while and is 'rattling'. I guess after say a 100 or 200 turns of the crank (the revs are around 200-300 rpm.) there is single a knock - maybe similar to a knock of a faulty shock absorber on road hole (it is 'felt' and heard in the cabin, front center left). But it happens when the vehicle is stationary. This Yaris (if not all) model has the touch ignition key start (continues with key released till the engine runs). The noise also changes in the sound kind and intensity. When I tried to record it after say 6-8 starts there was no noise. Weird. Thanks for help. Z

Edited September 25, 2015 by zegarnek