Clatter noise at startup. Heads up

Thanks for the update. But I don't think your service guy got it right. There is no oil in the intake manifold. What we were told was it was water/condensation build up in the manifold that would get sucked in during startup causing the misfires. The new manifold now has ridges that trap the water until is vaporizes later.

 

And that very well be where the clanking noise comes from (dampener) but the cause is the misfire. In fact many members here reported the error code (engine light) misfire.

Like you said, hope that fixes it. Be sure to chime in again if it does.

I had mine replaced in March and hope I never hear it again!

 

Well, you can get oil in the intake manifold, due to the Atkinson cycle "blowing back" some intake charge. This is why on the GII one thing lots of owners do is clean the intake manifold and MAF sensor.
It appears to me, reading this, that Toyota is still trying to fix this "clatter" issue, which is ongoing. Do a search and you'll find lots of posts from panicked owners. So a redesign of the intake manifold was done? Interesting. I wonder how many owners will get the new manifold.

 

can anyone help i have a 06 prius on start up all is ok when engine fires up i get a rattle a bit like a clutch rattle, this happens when it is charging ie the display show arrows from motor to elec motor to battery. the minute the engine is not charging and the engine is just idling ie no arrows on display the noise goes. it also only makes this noise in p mode every thing is working fine no fault codes nothing any ideas

 

I think http://priuschat.com/forums/gen-iii...n-engine-knocking-startup-t-sb-0012-10-a.html might be the condition experienced by the OP.

 

im afraid my prius is long out of warranty why does the clatter noise go when i select any other mode apart from park instantly i have been to the dealers here they give me a vague look kinda scary im sure they know whats going on, is it a costly fix??? prius has done 90.000km

 

We bought our 2012 3 HB In March of this year. Twice in May on different mornings (temperature both nights in the 60's) we heard a momentray mettalic clatter for a few seconds at startup. No CEL either time. I've heard the condensate caused knock and it cenrtainly wasn't it (it wasn't cold enough outside). It hasn't happened since and I hope it doesn't happen again but I'll keep posting if it returns.

 

The clatter noise in the GII is not part of this topic. It's not "normal" or common in the GII. In fact I've never heard of it. Are you referring to engine start-stop? If you put heavier motor oil in the engine it will "hunt for position" when stopping and be a little rough when starting. Make sure you are using 5W30 or so.

If that's not what you're experiencing, there is a "clutch" in the power train, used to limit torque impulses. Perhaps that's failing? It's a fixed clutch, with no release mechanism. It just slips when the drive is over-torqued. Though if it only happens in "P" I don't think that is it.

Does the transmission lock in "P"? If not, then the "park lock" mechanism has failed.

 

We had a terrible clatter at start up after the 2010 Prius sat for five months in a non heated garage, under the house. The temperature never drops below 40 degrees. The engine was stopped and restarted and the chatter lasted only a couple of seconds. The engine was shaking terribly and I assumed it was running rough because it hadn't been run for five months. The next time it started it clattered for a second and no more clattering after. Should we contact the dealer about it?

 

Hello everyone! My first post here. So, is this something to be concerned about, this very brief clatter noise on start up? If it’s just a slightly alarming sound that goes away quickly, but doesn’t mean that the engines going to be damaged or have any problems, maybe I don’t need to have anything replaced. What do you think guys? And girls?

 

Hello, and welcome to PriusChat. What you might be hearing is a 16 valve tappet chorus resulting from a drained-of-oil distribution pipe, maybe resulting from a stuck back-flow valve. I don't know for sure if your engine, or even my engine, has a valve like this to keep the upper oil gallery from draining. I think some sort of back-flow prevention used to be incorporated into the spin-on oil filters, which are no longer allowed. Someone else in the know may chime in about these symptoms. Or maybe there is a Prius V group with better answers higher up on the PC front page than Gen III? I don't look around much.