Engine Noise And Vibration - Prius Gen3

[kevin h]

This happened to me last weekend (I'm assuming the same problem can occur in the Auris HSD too?) I hadn’t used my car for a few days (it was under about 2 foot of snow) and I started it up. At first no problem, then a very loud banging and heavy vibration (bit like an engine misfire but seemed worse). I shut the power down straight away and popped the bonnet. I couldn’t see anything, but the thing I noticed was that the noise/vibration only appeared to start as the AC fan ramped up speed to defrost the windows. I tried starting again without the AC on this time and let the engine warm up for a few minutes before manually turning AC on and spinning the fan up one notch at a time. No problem this time and since then I have done several hundred miles without problem. I put it down to ice or similar on the fan blades.

GC – I also notice a motor hum for a second or two before the engine starts. I put this down the motor spinning the engine up to operating speed before actually firing. Having said that if it was a software update I would have expected the Auris HSD to have the latest firmware from the factory.

Hi,

I'd like to compile a list of people experiencing the problem.

My dealer has already passed on the details of one other to Toyota UK.

Assuming you went to tyour dealer, can you tell me which one. and if willing, give me yor Reg No.

Cheers

kev

[kithmo]

Not having experienced this problem personally (yet) I can't be certain what it is, but from what I've seen and heard on the internet via various forums, youtube etc, it looks like what used to be called Dieselling. This can occur when there is too much compression e.g. excess fuel or oil in the cylinders, sometimes accompanied by excessive smoke from the exhaust. It can also occur when there is a carbon build up in the cylinders, but his is highly unlikely on a low mileage modern engine with the better quality fuels and oils we have today. I suspect excess fuel would bring up a fault code on the lambda sensor but too much oil may not.

[Grumpy Cabbie]

Unlikely to be dieseling as it has often occurred on cars with low mileage. It first happened on mine at about 3k miles.

There is also a fix for the issue in the USA! and it isn't just the Prius engine over there. My Prius does not burn any noticeable amount of oil between services as you'd expect from a new modern car. If excess oil was seeping into the cylinders I'm sure there'd be smoke at start up and a reduced oil level?

[kithmo]

If excess oil was seeping into the cylinders I'm sure there'd be smoke at start up and a reduced oil level?

was there any excess smoke at start up ? I'm sure that on one of the examples I read of that they had excess smoke, typically, I can't find it now, maybe I was dreaming LOL.

There wouldn't be any noticable reduction in oil levels if it only happens rarely, e.g. 3 times in 37k miles.

What puzzles me, if my theory is right (and it is only a theory BTW), is where could the excess oil be coming from to get into the cylinder(s) affected.

[Grumpy Cabbie]

There was the white whispy smoke coming out the exhaust and that carried on for about a mile or so as the car was run. I'm sure that is just normal for a cold start in damp weather?

What's your theory?

[kevin h]

There was the white whispy smoke coming out the exhaust and that carried on for about a mile or so as the car was run. I'm sure that is just normal for a cold start in damp weather?

What's your theory?

GC's experience mirrors mine exactly.

I intend not to let this drop with my dealer or Toyota.

[mysecondavensis]

It happened to mine about a month ago when we had the start of this snow and ice. It was very cold I mean around -10C overnight. I had manoeuvred the car on the drive to let my son out and the engine had run for a short while, then I had switched off. A day later when I started the Prius it rattled and made a clattery sound like a bad misfire/valve timing error(?). I switched off, waited ten seconds and then started up again it ran OK and has given no trouble since.

(In fact my fondness for this car grows all the time: it has also been excellent on snow and ice.)

I believe the rough start up is possibly due to flooded cylinders after a short use with a very cold engine, although other suggestion is it sounds like no, or low oil in the valve gear because of the cold.

(I'll have to change my sig as I have had the Gen 3 Prius T Spirit since May 2010)

[kevin h]

It happened to mine about a month ago when we had the start of this snow and ice. It was very cold I mean around -10C overnight. I had manoeuvred the car on the drive to let my son out and the engine had run for a short while, then I had switched off. A day later when I started the Prius it rattled and made a clattery sound like a bad misfire/valve timing error(?). I switched off, waited ten seconds and then started up again it ran OK and has given no trouble since.

(In fact my fondness for this car grows all the time: it has also been excellent on snow and ice.)

I believe the rough start up is possibly due to flooded cylinders after a short use with a very cold engine, although other suggestion is it sounds like no, or low oil in the valve gear because of the cold.

(I'll have to change my sig as I have had the Gen 3 Prius T Spirit since May 2010)

The more I think about this, the more I beleive it "could" be something to do with a short journey not allowing the system to go through a full heating cycle.

On most evenings, I move the car from the drive into the garage, and on cold evenings this might cause the problem. I'll be monitoring that sinario over the next few weeks.

Should be interesting on Monday when the car moves for the first time in 4 days.

I've written to Toyota UK directly to highlight the problem and gave details of at least 4 other sufferers. Had a verbal response on Thursday confirmingan investigation and a promise to get back to me (Not holding my breath for to long)

We shall see.

[MG Nut]

Been to the main dealers about the (rare) knocking on cold start issue. Got their top dude to do the diagnostics and I explained exactly what happened - how the car had been stood for 3 weeks and started every 3 - 4 days and allowed to fully warm up each time etc etc.

He checked all the codes and there was nothing at all out of the ordinary (and even that was nothing special). When the knocking occured yesterday the engine started up as normal and ran ok but there was almost a slight hesitation, almost misfire like judder on 1 cylinder but it was ever so slight and eventually corrected itself after a few seconds. I reversed the car off the drive and stopped as I listened for this slight misfire which had now come back again and got worse and worse sounding like a definite misfire. It then seemed to spread as if missing on 2 cyclinders and then bang, bang, bang - it was running as if on only 1 cyclinder and physically rocking and shaking the car, so I turned the car off! Left it 5 seconds and turned it back on, the car rebooted and fired up as normal, running smooth as usual. No knocking, no banging and no clattering.

As you can see by the description it is not a slight vibration or a small rattle. The chief mechanic guy said if it was missing at all this would be reported by the onboard computer. If it was over fuelling this would be logged too as would under fuelling, yet the car was certainly not running as it should.

I think I'll go with the theory that it's a software issue to do with the valve timings being out of kilter due to the car being stopped half way through its warm up cycle the day before. This matches what other users have reported in the US and I did indeed only half warm the car up the last time I ran it about 2 or 3 days earlier as I was in a rush. Trouble is Toyota just don't seem to accept there is an issue and as it is so rare it's almost impossible to replicate and the onboard diagnostic system just doesn't seem to pick up on it. Maybe the car doesn't think there's a problem worth reporting as it thinks it's doing what it should be, when it obviously isn't (hence a possible software problem).

I am waiting for a hundred responses from owners saying they haven't had the problem so therefore it doesn't exist, but there are a significant number of reports of this issue and it would be helpful if only owners who have suffered this problem could report their experiences. That way we might be able to narrow down the circumstances surrounding the issue with the hope that something more detailed can be provided to Toyota.

Experience or theories from Toyota dealers/mechanics would be helpful too.

Cheers guys n gals

Hi Guys

Been reading your noise problems, could it be that the thin oil is draing back to the sump and leaving very little in the bores, what about putting some PTFE adertive in,

I have three old MGs 1953, 1964 and 1972 all with it in, my 72, when you hit 60 mph it made a noise, I could tell when it got to that speed without looking at the speedo,I put ZX1 IN it completly removed the noise, what it is supposed to do is stick to the bores, I have seen a demo, where it is put in, the car is run for a short time, then the engine was drained of oil, the engine ran on without oil for the rest of the demo, would it be worth talking to Toyota about it,its only in the engine,I do not know but I would not have thought it would stuff up the Hybrid system. what do you think.

MGnut

[capnbirdseye]

Spotted this which may be totally irrelevant to the problems you guys are getting re sparking only half the plugs at start up so maybe this may be something goes amiss and delays the other cylinders too long??

Quote:

Whereas a conventional car passes fuel and sparks to the ICE as soon as the starter motor gets it turning, the Prius waits until MG1 gets the ICE up to around 1000 r.p.m. This happens in less than a second. MG1 is much more powerful than an ordinary starter motor. To turn the ICE at this rate, it needs to spin at 3600 r.p.m. itself. Starting the ICE from 1000 r.p.m. puts virtually no strain on it because this is a speed at which the ICE would be happy to run under its own power. In addition, the Prius begins by sparking only a couple of cylinders. The result is a very smooth start up, free from noise and lugging, that eliminates the wear associated with normal car engine starts.

[Grumpy Cabbie]

@MGNUT, I really wouldn't want to put any additives in the gen3 Prius engine. It has very tight tollerances and really must use 0w20 oil. You will get driveability and hesitation problems using anything but that oil.

@CAPTAIN, This is what I thought at first - the engine doesn't fire upto full speed before the fuel is injected, but often (and also on the video I posted on page 2) the problem starts after a few seconds of running. In the video you can hear the motor whizzing the engine round until it hits the correct speed before it is fired up. The US forums think it is the vvti controller and/or something to do with the car being stuck in a certain part of the warmup cycle - having previously been stopped halfway through it. Why this occurs is still something of a mystery. Maybe it's mechanical, maybe it's software or maybe just a faulty part. Rumour has it that it has been fixed on later gen3's which is why not everyone has the problem.

Also, my car has been stood for nearly a week at upto -10c overnight most nights and I'm due to pop out in it today. Lets see if it's OK or not? Will update you if it's not.

[MG Nut]

@MGNUT, I really wouldn't want to put any additives in the gen3 Prius engine. It has very tight tollerances and really must use 0w20 oil. You will get driveability and hesitation problems using anything but that oil.

@CAPTAIN, This is what I thought at first - the engine doesn't fire upto full speed before the fuel is injected, but often (and also on the video I posted on page 2) the problem starts after a few seconds of running. In the video you can hear the motor whizzing the engine round until it hits the correct speed before it is fired up. The US forums think it is the vvti controller and/or something to do with the car being stuck in a certain part of the warmup cycle - having previously been stopped halfway through it. Why this occurs is still something of a mystery. Maybe it's mechanical, maybe it's software or maybe just a faulty part. Rumour has it that it has been fixed on later gen3's which is why not everyone has the problem.

Also, my car has been stood for nearly a week at upto -10c overnight most nights and I'm due to pop out in it today. Lets see if it's OK or not? Will update you if it's not.

Hi Grumps.

I am not saying put it in without consulting Toyota, it would not effect the oil, the ZX is ptfe in a suspension, what it does, it puts a few microns of PTFE on all the moving parts, they say that PTFE is one of the most slippery things you can get, It in fact should make thing move a lot better rather than stuff it up, but as I said if it was me I would ask Toyota about it, it could stop an engine failier if its a mechanical problem, just my opinion.

MGnut

[Sagitar]

Have a read at this before you go adding anything to your engine oil.

[Chris Dance]

PTFE additives are OK for old engines but I would not use any additive on a new engine. I think putting an oil additive in a Prius engine may affect the warranty. Toyota may not honour the warranty if anything went wrong with the engine.

[tore]

Hi Grumpy Cabbie

I have reported this problem last winter on PC ( US ) and according to what you have written, the shaking and vibration is very much similar to my experience. For me this happened after my return from a 12 days holiday in Tenerife last January.During those 12 days, the temp. had been between -10 to -15 degrees in the area at the airport outside Oslo. However, my car was parked directly after a 35 min. drive to the airport. So the engine was warm ( about 85 degrees( C )when stopped.

I informed this issue to Toyota distributor in Norway, and as I happen to know some people in their Aftermarked dept. I learned that they had already been informed by one of their dealers about this phenomenon during this very cold periode in Oslo area.

I was told that they would report this to Toyota in Japan as a QIR. Since then, I have not experienced this issue, but I have never rested my car during so many days in the cold. During my summer holidays, the car was parked for approx 12 days, but it started normally when I returned from my boat trip.

So, based upon my own experience, I doubt this to have any connection with stopping the engine not fully warmed up, and then starting after some time in the cold.

I`m more inclined to suspect some software issue related to cold temp. during a periode of time.

[MichaelM]

I went to start my Gen 3 Prius this morning and what a noise! Banging and clattering as though the engine was disintegrating.

I immediately switched off, left it a few seconds and tried again. Same problem. Tried yet again and same problem for a third time.

So as the hybrid Battery indicator was high I moved off under EV and VERY slowly accelerated. The ICE kicked in and was a bit rough

for a few seconds and then it all ran smoothly as usual. All is fine now.

The car had not been used for about three days but it was not particularly cold weather.

However, I had moved it a few yards under EV to clean it the day before.

Also what may be more important is that I have a vague memory of starting the car some days ago

and for some reason switching off before it had fully warmed. I think other owners have posted similar comments to this.

The clatter did happen once before during last winter but then it only lasted seconds and

I just forgot about it.

So that is twice in 9500 miles. I will have a chat with my local dealer Snows (was Kings) Toyota at Hedge End.

[bounce88]

I have a 2010 Prius IV which I bought about 4 months ago. I have experienced engine knocking/banging 3 times all in cold weather. Once it was extremely loud to the point I thought the engine would fall off. The car only has 2,600 miles and I have scheduled an appointment with Toyota next week to take a look at the issue. Hopefully they will find a solution to this as I am afraid it will cause further engine damage if not resolve quickly. I will keep you guys posted.

[MichaelM]

Called into my Toyota dealer today and asked them about the rattle/clatter.

The service adviser went off to have a good chat with a Prius Technician and I believe

he was genuinely trying to be helpful and not just fob me off.

He said they had only had one report of this type of event and in that case the rattle continued as there

was a problem with wrong or contaminated fuel being used. Definitely not the situation with my Prius.

He did ask if any warning lights had come on but I could not help on this as firstly, it always looks like a Christmas tree when

you start a Prius and secondly the noise so distracted me I never got to look at the dash!

My car is just fine now, so I will wait and see if it ever happens again and if it does I will

check for any warning lights and also note details of the circumstances.

[Grumpy Cabbie]

This is the problem you'll have. You're never sure if they're being genuine OR fobbing you off.

My dealer swear blind they're logged it and reported it to Toyota UK so there should be more than one case of the rattle in the UK (me!).

Check out the earlier posts and maybe check out the US forum too. Toyota know the issue but appear to be side stepping the issue.

[RobMagpie]

It happened to me last week. I had to shuffle two cars around on the drive so the petrol engine came on but did not complete its warm up. I did not use the car for anything else that day. It was coldish but not the excessive cold we have had. The next day on starting the car it was banging so I switched off and left it for 10 seconds, then restarted and was fine. No problems since but have always completed the warm-up cycle before switching off. This is the only time in the months I have had the car when I started it for a short time and it had the problem.

[kevin h]

Heared nothing from toyota since jan, but suddenly had a call.

I'm taking my car in to have a replacement Engine Manifold which should resolve the Engine noise issue.

We shall see, but its a bit hot to test it as it has only happened 3 times and each time on the cold.

Watch this space over winter and I;ll let you know

[Tom McGregor]

My Auris HSD sometimes starts with a rattle as noticed by other members. I have been told by my dealer that some parts require changing, including manifold parts.

This job requires the car to be in for a day.

Parts are now on order from Toyota. They seem to now recognise that there is a problem with the engine.

[kevin h]

Manifold parts.

Ditto what they did with mine back in Sept.

[r04drunner1]

Hmmm. You are not alone, Grumpy. I had the banging rattle happen on my 2010 T4 a few weeks ago, during a cold start. The car had been sitting overnight one frosty night. A very alarming noise, it sounded like the engine was being transformed into a basket of loose bolts!

I switched off the power, waited a few seconds, then switched it back on again. The car then ran fine and has done so ever since.

I can't recall if the Prius went through a partial warmup beforehand or not. It's possible.

Should I take this to the dealer? It was a while ago and the car has been fine since, so I am inclined to just keep a watching eye on things. And try to avoid doing a partial warmup cycle...

[Grumpy Cabbie]

Apparantly it's now a known problem with a cure. Condensation can form inside the manifold in certain circumstances and is then sucked into the engine when started (usually cold start - hence the condensation forming) resulting in the missfire and clatter.

Up to you whether you get it replaced. It's only happened to me 3 times and not for about a year - I think.