NEW!!! Service Bulletin for Engine Knocking at Startup T-SB 0012-10

I only have 45k on the odometer. I checked the brake fluid and it is above the Min mark. If you pump the pedal can you activate the booster/accumulator each time? Seems like all recalls are complete. It just came from the shop for the Knock tsb and recent inverter software recall.


iPhone ?

 

Initially I can activate the booster. Even driving, it will activate when pressing the pedal though there's no pattern to it. On my current as well as the previous Prius, the pedal is not soft. Someone must have seen this problem and will no doubt come in here and address it.

 

I just checked an online 2010 owner's manual and the procedure should be on page 48 of your manual.

 

It seems like I can exhaust the booster capacity. After driving my old 5 series bmw and our brand new sienna minivan, the Prius just seems really soft just sitting in the driveway and pressing the pedal. That's when I triggered hill start and freaked because of the indicator lamp. I'll check again tomorrow. Seems odd to be able to exhaust the accumulator and keep triggering it. Maybe that's the way it works!


iPhone ?

 

Awesome! I looked in the back of the manual too and it shows it as customizable and maybe that threw me off. When at the dealer they were supposed to change it to open all. I went to car to check and no dice. So the dude grumbled over with the Panasonic tough touch book pc and plugged it in to the port. And nav over to the option. Maybe they can get to it that way too for faster changes. To the original topic, the starting and stopping of the ICE is somewhat smoother with the new motor mount. Not night and day but noticeably better.


iPhone ?

 

Awesome! I looked in the back of the manual too and it shows it as customizable and maybe that threw me off. When at the dealer they were supposed to change it to open all. I went to car to check and no dice. So the dude grumbled over with the Panasonic tough touch book pc and plugged it in to the port. And nav over to the option. Maybe they can get to it that way too for faster changes. To the original topic, the starting and stopping of the ICE is somewhat smoother with the new motor mount. Not night and day but noticeably better.


iPhone ?

 

Got the tsb on just picked it up..intake put on is 17120-37054...see attached for full invoice. Looks like this won't silver my issue based on others accounts. Cold weather back the next 5 days I'm going to retest see what happens.

 

Good luck!

 

What Steve said! .....

 

oh I'm assuming it'll continue to happen, i'll be ready with my phone to record it when i test. I also assume if i go back to the dealer with the issue the dealer will basically tell me to shove off.

 

Likely. Just follow the work arounds given to avoid embarrassment with neighbors and co-workers like the rest of of us have.

 

The intake manifold was replaced on mine on 2/18/2014. However, comparing my invoice to yours, my invoice does not have two lines that yours does. (1)Gasket for intake manifold and (2)Gasket throttle body. I wonder if they reused or replaced and did not invoice.

 

Hi there rrg,

Of course! But I'm curious about your suggestions.

You suggest changing to 93 octane with Heet. What is the reasoning behind this?

I'm afraid it doesn't make sense to me. 93 octane is more difficult to ignite, because it's intended to resist auto-ignition (detonation, pinking, knock, etc). By all accounts, the problem is caused by water in the intake manifold, whether due to condensation or manifold icing in the right (wrong!) conditions. Evidently, some of this water is sucked into the cylinder(s) at start-up and on to the spark plug(s), causing misfiring (non-ignition) and running on less than 4 cylinders. So changing to 93 might make the problem worse, and cause it to continue for longer, while the spark plug(s) dry out more. And, if there is moisture in the fuel, Heet will likely make ignition even more difficult, because the fuel will contain emulsified water as well. Both things would seem to exacerbate the problem.

I agree with trying to change the load on the engine, but believe that putting the trans out of Park and into Neutral is more likely to work, because that will take out the Regen load, and reducing the load will reduce the amount of fuel being injected into each cylinder. Reducing the amount of fuel per stroke will mean that each working cylinder will generate a smaller rotational impulse to what is apparently a resonant system. This will smooth out the ICE crankshaft rotation, and may be enough to eliminate the knocking, or at least, reduce its severity.

If that doesn't work, go back to Park and apply the Gas pedal! Don't go into gear, as the car will want to move...

 

I am not an auto mechanic so I do not have the background to explain what might be happening.
I am only documenting my experience for the last 3 winters with no shakes on the original IM.
I changed fuel habits after seeing it happen two times the first cold months in 2011.

I have 50K miles on the car now and I still cringe and cross my fingers in the cold single digit mornings when I push the start button.

Of course I never advocate a fix, so let us know if you find something that does or does not work for you.

Also there appears to be two kinds of shakes being reported. A smooth one, like engine pinging (see youtube) and one louder that sounds like banging parts in the engine bay.
The smooth one happened to me.

my2cents

 

FWIW......I purchased & replaced my I/M way back with the first upgrade (#xxxxxx-xxxx-52)......at that time the upgrade I/M came with all gaskets already installed.......again FWIW.......oh, & by/the/way, the upgrade fixed nothing! .......

 

All,

It should also be noted some cars just appear to be more prone to this rough start thing. Again we owned two 2011 prius cars and one does it all the time, the other, NEVER.
Just got a call back from the dealer on mine that is in the shop for this repair! Toyota has no repairs at this time, that is directly from the regional toyota rep. Not sure how to proceed now".....

 

Might be a silly question.
Do the VIN numbers indicate they were made at the same location?
Japan (Kariya or Tsutsumi)

 

Yep, same plant within a 100 cars apart from same line".......go figure

 

Strange is right, who would of guessed they were so close and yet so distinct with this issue.

It's nice to remove a small possibility related to a single plant.
Thanks.

 

i got to thinking i would if this issue could avoided if toyota had implemented a high-rev cold start on the prius? i have been told they do this so the oil circulates faster. our 11 rolla has essentially the same engine, same im and has not had the issue...