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

I leave mine on for about 5 hrs with the goal of really heating up the block before I leave for work around 5:30 to 6 AM. No one ever mentioned a time limit for its use, AFAIK.

 

Unless it's really cold I've found temps plateau around 2 hour. From 1.5 to 2 it's almost plateaued. This is monitoring with scangauge. Prolonged times, I'd monitor the connection at the extension cord. I've noticed it can get a bit warm, I think more so if left on for protracted time.

 

I am wondering if plugging the engine heater in costs more than just starting the car and driving off.
It would seem the gas used driving off also gets miles and heats quickly too.. so the heat is free (or the miles are free).
Whereas the electricity used to heat the engine only gets a warm car.

Using the 0w-20 or 5w- 20 gives almost instant lubrication when driving off cold. Especially synthetic.

 

Our rates work out to about 6 cents an hour IIRC. Use it almost without exception, for first start of the day. Makes for a babied engine, and has the engine shutting down noticeably sooner.

 

So I'll reset the timer to only run for two hrs before I need the vehicle in the morning.

I think of it as charging my Prius but with thermal energy.

 

Just an FYI to everyone in cold climates, my '10 exhibits this behavior every few days, usually in 85 degree weather or hotter. The issue doesn't seem to be isolated to cold climates :-/

 

Under warm weather, if you move it under electric and stop before the engine starts, for example washing the car in the drive way and moving it slowly into the garage, the engine rattle happens upon start the next time. It's a little tricky to reproduce it.

my2cents.

 

Has any dealership fixed this problem under the TSB with more than 150k miles? I'm at 177k and it happened to me this morning.

 

I have 2010 gen3 Prius. My engine started knocking today 5 seconds every time it starts or kicks in. But at same time it also started giving shakes every time it goes from ev to gas engine while driving. It drives fine with ev and with gas engine, but transitions makes it shake and knock. Any ideas?

 

Welcome to Prius Chat .Can you give us more information about your Prius such as:

• Mileage?
• Owned since new?
• Any oil consumption?
• PCV valve changed out?
• Try any fuel injector cleaner?

You get the idea.

Keep us posted.

 

Mileage is 250tkm so about 155t miles. I have owned it for 2 years and drived 50tkm. I usually have to add one liter of oil between 15tkm maintenances. I really dont´t know if the PCV valve has been changed out, but I think I start with fuel injector cleaner

 

I have a 2011 with 146k miles I've owned since January. Last week it started doing the loud knocking thing at startup (weather is quite warm here), and it has thrown P0301 and P0302 codes. According to the service records for the car, a year ago the previous owner took it to the dealer with a CEL, and the intake manifold was replaced. I haven't done anything with the car except oil and filter change, and fluid changes.

It sounds like the intake manifold isn't always the cause of the startup knocking, is that correct? Can someone familiar with this problem please let me know an orderly way to troubleshoot this before I just start doing willy-nilly replacements? Thanks so much!

 

How many miles have you put on the Prius since January? What maintenance has been done to it (spark plugs, Throttle body, MAF sensor cleaning, etc)? Is there any oil consumption? What is your mpg like and how is the Prius used (mostly highway or in city driving)? Changed the air filter recently?

There are components before the intake manifold, so those components would be good places to start.

 

Thanks Ray,
The spark plugs have about 20k on them. No oil consumption, and the air filter has less than 10k on it and looks clean. My daughter has put about 2k miles on it since we bought it, all city, and we are getting 42-46 MPG. I'm not aware of anything being done to the MAF or throttle body, nor the PCV valve.

Are those things that definitively can cause the knocking on start up? It knocks like some of the YouTube videos I've seen, loud knocking and shaking until I give it gas or put it in gear.

 

What do those codes point to? Head gasket? Google:

toyota trouble code p0301 p0302

Or maybe EGR clogging?

 

They all can.

Is it losing any coolant? Are you the DIY type? I would pull the egr pipe and see the condition of things. Ultimately though, you're dealing with an air fuel mixture imbalance.

 

Fuel injector cleaner didn´t help. At maintenance their first guess was spark plugs and they changed those but it didn´t help. Plugs were very old so I think it was good thing to do anyway. Car still makes loud knocking noice at start (lasts few secs) and occasionally shakes when engine kicks in. PCV-Valve next I guess?

 

The ugly possibility is a blown head gasket that's allowing coolant into one or more cylinders. Engine coolant should be dropping but perhaps slowly.

Here's a suggestion: have an oil sample analyzed by Blackstone. Siphon out some oil from the dipstick tube. I use a Mitivac hand vacuum pump pulling the oil thru some clear tubing that fits down the dipstick tube. Send the sample to Blackstone for analysis (they will send you sample bottles in mailers). If they find excessive amounts of water in your oil, you likely have a head gasket problem.

 

After a LOT of reading in this thread....I guess I'm a head gasket issue too. Sealant time again?

 

My 2011 with 72k miles recently started sputtering/shaking at start up...when the weather is cold and damp. Took it to dealer and they said that the codes were showing misfiring in cylinder 1 (P0301). Dealer pointed to this TSB and said to replace the intake manifold ($600). Reading this thread, it sounds like replacing the manifold might not solve the problem that it might be a head gasket. What should I do? And will Toyota headquarters do anything?