1.8L starting rattle, knock, events

My 2007 did this a number of times. Scared the %*&^ out of me the first time as it wasn't that cold! But, it seemed to not be anything out of the ordinary. Just weird. It's got 157K on it as it's being passed into the hands of friends this past week... in great shape!

 

:jaw:You mean you don't get a demo! What kind of cheap dealer do you work for LOLeace:

 

LOL!!
Uh no, in CA there are not too many demo cars still running around.
Things have changed a lot with insurance and dealerships' deep pockets.
Frankly, I am happy not to have one. For obvious reasons!!!

 

So....I can add myself to the club, it seems....and looking at the number of posts in the past month or so it is happening more and more often...

I took out the car from the garage Sunday to vacuum it (before winter comes) after last using it several hours before on Saturday. I turned it on and I could not put it into EV (battery low). So the ICE kicks in, and after a few secs I need to turn off the car as I drove it out of the garage. I do my cleaning. After about 20 mins, same thing - I turn it on, the ICE fires after a few secs and I park the car in the garage and turn it off after another few secs.

Both cases nothing weird happens. Also it was the first time since 2 years I own the car that I turn it on/off so quickly, twice!

So then I take it Monday morning to go to work. The first weird thing is that the hatch lock opens "slowly" (I had a weird feeling about it) - I thought "the 12V battery is not charged enough"... Then I get in and turn on the car - the ICE kick in but really weirdly, like as if it doesn't manage to spin up - it last 1-2 secs at most, then it runs as usual while I take the car out of the garage.

Then I need, as usual to get out of the car and close the garage door, and that's when it started rattling... I was looking at my Prius like "You are doing it! you are!!!! My precious is *also* doing it!!!" - it lasted 2-3 seconds and it wasn't as loud as I saw on the videos here. Then honestly pissed off, I drove to work.

The evening I took the car again to drive back home and it started weird again, but no knocking sounds, at least for what I could here from inside the cabin.

Today, all fine - as if nothing happened.
ODO: 39.000km - Temps around 10-15C (nothing really cold, that is).

I have a (possibly stupid/nonsense) theory: if the HV is low (2 bars) and you do an ICE start up that you cut off too quickly, the energy required to spin the ICE is not recovered completely and the VVT timing is not correct for another start up, since you turn it off "too soon". It's like as if there is a bug in the software of the VVT that does not reset the timing for ICE start up when the ICE warm-up sequence is interrupted abruptly. The fact that the hatch lock opened "slowly" seems to show that the 12V was also not at it's max (another drag/load on the HV battery at ICE start up when you turn on the Prius and get the Ready on).

So if you park the car with 2 bars then after 8+hrs you do a quick ICE on/off, it seems there is a bug in the VVT timing, and possibly a lack of energy in the HV Battery to allow a proper ICE start that the VVT timing cannot recover properly (my ICE sounded pretty slow compared to normal when I turned it on Monday morning, before the knocking occurred). It goes all "bezerk" and you get the knocking. When you press the gas and you rev it up, you are forcing the engine to warm up not focusing on reducing pollution, but requesting power and hence forcing it out of the warm-up cycle and VVT timing changes completely. When you release the gas likely the VVT timing is back to "normal" and there is enough energy now in the HV to avoid any subsequent ICE quick on/off cycle problem (plus the ICE will be warm this time).

To me it looks more like a SW issue that cannot "recover" properly VVT timing and/or weak HV battery, if the ICE warm-up is interrupted before X secs.

Let's see what will happen in the next few days...hopefully nothing similar again. My warranty expires Sep. 2012 and I can extend it another year at least....thinking about it now...

 

PS: my rattling/knocking event was nothing like this one posted on this thread.
It was much much shorter (2-3 secs) with no repetitions and probably as loud as the first train of rattles in the video, rather than the second train.

 

Just happened this morning to my 08 Prius for the first time. Have had the car for for a year and a half. Has 42k miles. Was blowing leaves off the driveway Saturday morning. Moved the car forward about 20', turned off for 5 minutes, moved back, ICE was running when I shut down. Car sat til this morning, sounded like a bucket of bolts for a few seconds, then ran fine. Went 5 miles to post office. Shut off for 30 seconds, started fine, drove 18 miles to work. Came here looking for info, found lots. Will let engine warm up fully from now on.

Eric

 

Mine has rattled twice sounded like a car missing a spark plug. Will tell my dealer about it22189 miles

 

Just happened to me yesterday. 2010 IV with 45k miles. Temp about 50 degrees. Started car to re-position in garage. On EV power, back and forth about 20 feet total and less than 30 seconds to do. Shut car off....no problem. 45 minutes later started car to back out of garage and clunking noise started as soon as the ICE kicked in. Scared the s&^t out of me when I heard it and immediately shut the car off. I popped the hood expecting to find broken stuff or at least oil. Sounded like someone was bashing a sledge hammer to the engine. I have driven the car since and no issues. <<Sigh>> I hope this is not one of those gremlins that never gets identified. :/

 

Mine happened again, cold morning after weather change. Car had been moved a short distance the night before.

 

Think you guys may have something in the "short on/off" sequence before the car does this. I have a 2010, manufactured in either Sept. or Oct. '09, and have had it happen only two or three times. I doubt complaining to the dealers, or Toyota will do any good. And expecting them to be able to duplicate the event "on demand", well...........Ha!
I've now had my Pri 2yrs, 48K. And it hasn't happened in probably the last year. But I do think it has some connection to a short/brief startup and shut down. One where the ICE gets started then quickly shut off. I like some others wish there was a button you could push to "absolutely" not allow the ICE to start for the very brief positioning changes you may do on the car. I had been known to push my car out of the garage years ago, instead of starting it up to move it 20'! But now I'd let a vehicle run, or take it around the block, or something like that, instead of starting one up just to move it into the garage.
Of course I still can experience the "pucker" you get when you go over a bump while braking, and I had the "flash" software update done a long time ago. I just know it is going to do it, and try to be ready, or compensate.........!
But I do hope I never experience the "Start-up Rattle" again, that was disconcerting! And just knew it was doing the engine no good.

 

I've had it happen a number of times, and each time it was after washing the car on a Sat or Sun, (movement consisted of backing out of garage about 15 feet, then back into garage) and then letting it sit for the remainder of the weekend before driving to work Monday.

I'm sure Toyota is very aware of it, just like the front brake caliper rattle.

What I get sick of is the dealerships acting like they have no idea what you are talking about. It's the deer in the headlights, duh look.

Let's hope there is no damage that will show up after warranty expires.

 

I just had the terrible knocking start today on our 2010 Prius V. It didn't do it last winter at any time. I had it happen the first winter 3-4 times. After maybe 5 seconds or so I stopped the ICE and then restarted it with no noise on the second start. It sounds like a cold diesel engine starting up to me.(I have a lot of farm tractors) If Toyota knows why this is happening they are not coming forth with any answers in over two years. I just hope it isn't harming the motor somewhere down the road.

 

Just to let you guys know Toyota does know about it, and they have isolated the issue there will be a tsb coming out soon to fix it!, i'll let you know when there is more details.., mine did it too btw...

 

Hallelujah!!!!

 

Eldiee:
Are you anywhere near Ft. Madison?

 

Just like the brake caliper rattle issue I reported on waaaay back in 2010!
I hope you are correct, as the dealer I go to is completely clueless on this issue.
(Cabe Toyota in Long Beach CA)

 

I have experienced the banging at start up three times. I also took my vehicle into the dealer and service manager stated that she had not personally heard of that complaint. She had zero interest in capturing my reported symptom and logging into their structured problem solving database for later analysis.

 

Yea, most dealers are..., you'll be surprized how little dealer personnel know about this car...

 

I just went through this BS at my recent 5,000 service. The service writer hadn't a clue. The mechanic did try to replicate the problem but couldn't (no surprise). I think the next time I go in for service or the next time I hear the noise I'll bring 2 sound clips of the noise for them to hear. At least my complaint is on the service invoice. Hopefully it makes it to my vehicle history.

 

I am north of the Quad Cities on Highway 67 along the Mississippi