Rough Engine Start? Knocking Noise At Startup? There May Be Hope Yet...

I encountered this exact problem on my 2010 this morning. It was a chilly morning but certainly not the coldest we have had since I've bought the car last February. As soon as the ICE started, but knocking and vibrating began. I quickly turned off the car and looked under the car and in the engine compartment for any possible obstructions. Finding nothing, I restarted. The knocking began immediately again. This time I left the ICE running and looked under the hood. The noise seemed to be concentrated on the driver's side of the engine.
After around 10 seconds, the vibrations lessened then shortly thereafter stopped.
I had remembered reading a similar thread some months back, hoping this issue would never happen on my car. My concern is that amount of knocking has to be damaging something.

 

I'm still without Prius. I took in monday. They dismissed problem as a simple misfire and broke my windshield in the process. I notice how quick the dealership is to downplay the knocking noise to a simple misfire. I'm afraid Toyota may have to do a pretty good size lemon law buy back. If there are this many of us complaining about the same thing. I have always preached the gospel of how fantastic Toyotas are, but maybe the reliability train left this stop a few years ago. It's alot to swallow when the same people you try to stear away from certain brands say " looks like you should have bought a ------ like I did & i have no defense for toyota.

 

"They dismissed problem as a simple misfire and broke my windshield in the process."

That really sucks! Your car is at the dealer for one problem and they give you another bonus problem. I'd give that windshield r&r job a meticulous review before accepting your Prius back.

 

I know right? The only way to perfectly install a windshield is by the robotic arm at the factory. Totally crappy of them IMO. I guess I'll just have to video every startup to better document this for the DS. Honestly this DS is performing better than the DS i bought tge car from. Jim Norton toyota in Tulsa , ok atleast gave me a loaner car. Riverside Toyota where I purchased my car pretty much told me i can leave my car and Rent a corolla for $30 a day in a smart a_s manner at that. I must say customer service between Toyota and Lexus is like night and
day. Atleast Lexus acted like they cared and addressed my worries and concerns. I just hope we get tgis figured out before my warranty runs
out. No, i did not purchase the $4k extended warranty. It's a Toyota,
not a Kia..

 

I've toured numerous auto plants since 2001 (Toyota, Ford, Nissan, Mazda and NUMMI) and I recall seeing many of them installed by people, not robots. One of them included a tour of the Tsutsumi Toyota plant where I saw 2nd gen Priuses being built, in late 03.

Yes, I've seen footage of windshields being installed by robots. It's just not as widespread as you think.

I was actually semi-surprised by the amount of manual assembly even at Japanese auto plants in the final assembly area. On the other hand, the Hyundai plant mentioned at http://hyundaisantafemessageboard.y...ured-on-quot-modern-marvels-quot.html?page=-1 (I saw the Modern Marvels ep) has a LOT of work done by robots.

For someone who has visited a Toyota plant more recently, esp. one of the plants where the Prius is built, it'd be interesting to know whether windshields are installed by robots on Priuses.

 

Assuming the tech is properly trained and the right glass is used, there is absolutely no reason a replacement windshield will not be as good as the one installed at the factory by technicians. Over the years I have had numerous windshields replaced (lived on an island and had lots of rocks thrown my way). They all were perfect (no leaks, rattles, etc.)

 

FWIW I read my manual lately and it unequivocally states that warranty service requiring an overnight stay--not the result of either your or the dealership's scheduling, though--will grant you a free rental.

 

I have a 2005 Prius 170,000 miles (273.5 km) driven so far.

Experienced rough cold start up for the first time a couple of weeks ago. It only happened at first start up and only for a few minutes. Felt like a cylinder was not firing. Couple of days of this and the check engine light went on.

Took it to the dealer (Manhattan Beach Toyota, California). They had to keep the car for a couple of days because the symptoms were so short and only when the car was cool. They needed to make some measurements to be able to get some idea of the problem. Ended up replacing all 4 coils and spark plugs. Two coils were measuring out of spec and a third one was boarder line.

A week went by and car started up fine. Then the rough start started up again. No engine light warning this time. I took it to the dealer again. They kept it for another couple of days to run some tests. They even requested the Toyota Corporate Engineers to come over and take a look at the car. They determined that the Mass Air Flow Sensor was dirty. So they cleaned the sensor and area around it and did some calibration adjustments. It has been a week and the car is starting up fine.

 

Unfortunately, that sounds a little like they're just throwing parts at the problem. Maybe MAF but I'm guessing no, but hopefully the problem won't recur.

 

Refering back to the original problem on this thread, some of you might be interested or concerned to note that the European Auris Hybrid model is also suffering from knocking at cold start!

The Auris is a Corolla sized European built model with the hybrid side based on the gen3 Prius. The UK forums are now starting to fill with the odd owner suffering the "knocking at cold start after being left in the cold for a few days" problem. This would indicate a design issue rather than outdated software as advised for the Prius as the Auris has only been released here from July 2010! Also, my money is on a design issue as the Auris is built in the UK, using UK built components and UK built batteries. There is no connection to Japan other than the design, so it can't be related to a dodgy batch of components left over from early Prius's.

Anyone got any comments?

 

It looks like we are doubling-up on this topic. Grumpy started another one on exactly the same issue. Perhaps they should be combined?

Tom

 

Ooops sorry. I thought I'd do one for the International Owners too. Should they be merged?

 

I had my prius 2 2010 for 2 months. I have had 8 rough starts that sounded like the ice was running on 2 cyl. In green Bay this morning it was 10 deg outside and I started and stopped the ice 4 times before it started to smooth out. I am bringing it to Le Mieux Toyota again for this problem. They want to keep it overnight to see if they can duplicate the rough start in the cold wi. morning. Larry

 

Not necessarily. It's only a thought.

Tom

 

Is the noise coming from the left side of the engine is associated with lubrication of the timing chain?
Maybe before the oil reaches the chain tensioner can hear this sound?
I found an interesting article on oil and timing chain:
Are You Ready for GF-5 Oils?
An interesting part of this article:
" The Japanese auto makers would also like to see a new timing chain wear test added to the GF-5 specification".
and
"Another concern is that some of today’s GF-4 oils may not lubricate timing chains adequately, so a chain wear test or roller follower test may be added to the GF-5 standard. There has also been discussion about adding an oil aeration test that would measure the effect of air bubbles in the oil on lubrication".

 

i have had 3 different occasions this happen to my prius told my dealer and he claimed he never herd of it!!! hahahaaaaa

 

My first post here. I've had this same thing happen to me twice but only when I'm parked in my garage. It sounds like the earlier post about moving the car a short distance then shutting it down the night before is likely whats happening to me. Driving the car fromt he street into my driveway the night before, next morning rough start! It's currently at Prestige Toyota in Mahwah, NJ. Hope they can diagnose.

 

It appears the problem has been identified. Refer to this thread:

http://priuschat.com/forums/gen-iii...722-1-8l-starting-rattle-knock-events-13.html

Tom

 

Not quite. The TSB (which I posted on this forum several weeks ago BTW) is for 2ZR-FE and not 2ZR-FXE. It's probaly the same problem, but Toyota did not officially admit it yet.

 

Check out this video.
[ame=http://www.youtube.com/watch?v=nJJaMTyN-Ao&feature=youtube_gdata_player]Gen3 Prius Rough Start - YouTube[/ame]