Reproducable knock?

Well, occasionally my car knocks when the ICE is turning on when it's cooler out but only for a second.

It also knocks when the ICE shuts down when I let go of the accelerator pedal.

Yesterday, It had been parked over night the temp was 32 degrees F and when I started it, it knocked so bad it actually woke neighbors. I swore the engine oil should have been all over the street. 30 seconds of the fifth worst knocking I've ever heard. 4

The other 4 times I heard an engine knock that loud, were on 4 of my track and race cars when the engines spun main bearings, or sent rods through the side of the block. It really is unbelievable that so many instances of this cold knock happened and even those with new intake manifolds still experience this.

 

Yeah, that about sums up my experience with the knock. It was horrendous.

But since the IM replacement and the mount replacement I have not had it. But then we have a very dry environment and I am thinking it has everything to do with the level of humidity.

 

well, I did wash my car quite thoroughly the evening before this happened. The next morning is when it sounded like a freight train*

 

In the course of washing it, did you start/run it for just a few seconds to move it a bit?

 

Actually, after I washed it, I backed it up about 8 feet and the engine started for a few seconds, and then I shut it down and didn't start it until the morning 10 hours later in 32 degree temp.

 

My wife and I have been forced into a regimine of resisting short cold block moves of our '11 unless we absolutely have to do so, and if we do, we let it run a few minutes before turning it off. Sad that we have to coddle a third generation product like this. Sad there is more than one way we feel better about our '07 than our '11.

 

Well, I have a PiP with ~3500 miles, and it just happened to me this morning. Several days ago, I had to move the car several feet, didn't realize wife left the HVAC turned on, so the engine started up. Since I was in a hurry, I couldn't wait and sit there so the engine could warm up, so I proceeded to turn it off several seconds after the engine started up.

2 days later (this morning, first time anyone drove the car since the move), I get ready to leave for work, and sure enough, a rapid clicking sound (almost like a dead battery, but louder) matched the beat of my heart for 5 or so seconds. Having read about this issue on reddit just yesterday, I figured out it's just this noise issue everyone else mentioned, so I proceeded to go to work, and haven't heard it since.

Outside temp was in the high 20's.

 

Had this happen 4 or 5 times now on my 2012 v.
Most recent was yesterday. Outside temp was -5c, humidity around 55%.
I did wash the car the day before and it sat overnight at home, started up ok in the morning drove to work 30 mins on the highway. Parked at work. Humidity could much higher where I park at work as it is a thermal power plant with large cooling ponds nearby.
Car sat 8 hours, block heater plugged in all day. Started car, soon as engine fired up horrible knocking, I shut it down quickly, waited 5 secs then tried again, knocking again so shut it off again. Tried 3rd time and still knocked for about 5 seconds so I just pulled out and drove away. 30 mind later cruising on the highway I arrive back in the city, fuel was low so went and filled up. Right after that, drove around the corner to grab something to eat at a fast food drive thru. Engine shut off while pulling through and ordering my food. When I pulled up in line at the pay window the engine fired up and rattled/knocked lightly for 5 seconds, then settled down.
After that the rest of the drive home wash good and has started fine so far today.
Really getting frustrated with this issue now.
Car has been great other than this, but if Toyota can't solve this issue soon i'm almost considering trading in for something else that doesn't rattle and knock

 

I have a "work around" solution that is effective with my Prius, some others have tried it and it worked for them also, some reported that they tried it and it didn't do any good. But give it a try, it's free and it won't hurt anything.

As soon as you hear it start to knock push the throttle clear to the floor, on my car this stops the knock immediately. It only increases the RPM by a few hundred but it changes the amount of fuel and air going to the cylinders and clears up the knock.

Another thing that works for me is, when the car is cold, push the throttle down to start the car as soon as the Ready light comes on instead of waiting for the 15 second delay. I have never experienced the knock when I do this.

 

For myself, to now realize that "Toyota" of ALL mfgs., completely missed (or decided to ignore) this issue in the final "Count/Down" before production release, is a HUGE let/down!......

 

This happened to me today for the first time. Car was purchased used w/~65000 miles on it, now has 72000. Obviously out of warranty.

This, plus the many rattles and squeaks, have completely soured me on the Toyota brand. I'll never buy another.

Funny, my last hybrid, a Honda Civic, disappointed me so badly that I'll never buy another Honda, either.

Guess I'm just not cut out to drive these things.

 

We have it: last trip 40 miles of commute, parked 10 hours, temps >32. Knock is becoming more persistent at start up now, than it was last winter. ( I start my wife's car for warm up, before her morning commute.) Unnerving.

 

how many miles on her?