Motor shakes when it first starts up or takes off

exactly the same noise coming from my car i dont know what is it and it doesnt last long after engine warm it gets smooth , can any ody

 

hi
my prius 2009 3rd gen making a same noise and its just started last week when the weather went colder and i dont know what is it , but its only happens for 15/20 seconds when the engine is cold then also only on idle position , then car runs smoothly i have done my complete motor vehicle test yesterday and straight away it went pass no problem at all . .. can anybody help me in this regard ?

 

The best thing to do is to avoid the conditions that make it happen.

So, do not allow a cold engine (ICE) to start and run for ONLY a few seconds and then powered off and allowed to sit for several hours (usually overnight). It's upon the next start up that the noise/rattling occurs.

If yours is doing this in other conditions, you probably have a different issue (spark plugs, coils, fuel, etc).

GOOD LUCK!

 

thanks i ll try not to drive in that noise to switch it off if its make noise then start in a bit . is that ok ? its only happens when engine is cold .

 

Were you able to resolve this issue or is it normal for the Prius C? My 2012 Prius C does the same thing at every cold start. i switched from 91 octane to 87 and it seems to reduce the violent valve noise at start up but it's still some what loud. stops after about 15 seconds

 

my 2012 Prius C does the same thing at every cold start in So Cal. Has it caused any damage over the years?

 

This is a very old thread but no this doesn't hurt the car but I still never liked it when it did it!
You usually only see it in after the car has sit for days without being fired up.

***When it happens usually the fix is to simply immediately kill the engine then restart again.
Most of the time it won't do it the second time , if so kill it again and retry.

91 octane or higher is a waste of money on a small engine with a low compression RATIO and could even be junking up the exhaust.

Higher octane explodes slower.
This allows the explosion to last the whole travel of the piston down the long cylinder of a high compression engine rather than the explosion being done & finished before the piston has reached the end of the cylinder.

In the latter case the momentum of the other pistons carry it through to finish its travel....at any rate, IT'S LESS efficient using the slower burn high octane as some of the explosion is still going on when the piston ends it's travel and the valves open.

Not only are you wasting unexploded gas out the valves, but your also throwing things out of balance just a tad and could actually be adding to the problem of the misfiring vapor lock type reaction.

Toyota acknowledged there was an issue but didn't recall since there was no harm and it wasn't consistent.

Usually ppl that use their car everyday never see it.

Lots of videos on the subject.

Also lots of Prius Chat discussion.