Cold Start Knock Rough Running

[grahamh]

HI

I have 2010 model Prius in 2012 garage fitted new inlet manifold to cure rough running and knock from cold start.

Moved car yesterday ice started really load knocking and missing worst than before any ideas?

[kithmo]

Did you move the car previous to this move and the ICE started ?

Whenever the ICE starts you must let it run through the first warm up stage, that is, with the heater off, let the engine run until it stops by itself. It's less than a minute IIRC. If you don't do this you may leave excess fuel in the manifold which could cause the knocking when you start up next time as it's overfuelling.

Another thing that causes overfuelling is a dribbling (leaking) fuel injector.

[Grumpy Cabbie]

Dunno. The new manifold sorted mine. I experienced the knock a few times, then it was upgraded and never happened since. I do believe there's a software patch to stop it too. I trust you have a full Toyota service history where they can apply these patches?

[grahamh]

Did move car to have access to garage .

Have full Toyota service history last service July 2014.

Ecu flash recall has been carried.

Warranty ends June 2015

Will speak to dealer,concerned expensive repairs after Warranty expires.

[MEP's Yaris GS]

Did you move the car previous to this move and the ICE started ?

Whenever the ICE starts you must let it run through the first warm up stage, that is, with the heater off, let the engine run until it stops by itself. It's less than a minute IIRC. If you don't do this you may leave excess fuel in the manifold

Can't say I follow the logic here, a cold cycle shut down should be no different to a warm cycle shut down, injectors stop injecting an the engine shuts down surely?

The later is plausible though.

[Grumpy Cabbie]

Without going into the technicalities it is due to the car being shut down during the first couple stages of the warm up cycle in cold damp weather, often when it has been sat for a few days.

Google it on priuschat - hundreds of posts.

As a cheap 'fix' it is easier to use EV if you're just going to move the car 20 feet off your drive etc. Not ideal, but that's how it is :)

[grahamh]

Hi

Switched off before engine went through warm up cycle .

NEVER had a problem in all my other cars i have owned over the 45 years of driving that includes numerous Toyota from 1987.

Dealer fitted manifold to cure this ,should not happen.

Ev was selected but Battery was low so ice started up.

[Grumpy Cabbie]

There is a further fix out there somewhere and I believe it's software related.

There were loads of reports of this cold start misfire back in 2010 but after the fix there are barely any. I wonder if your software is not fully upto date?

[Devon Aygo]

There are two fixes for cold start ICE rattle/knock

1. For noises occurring at temperature above-10 degrees C which involves fitting a Modified intake manifold this was ultimately fixed in production Late Nov 2012 for Prius ( incl PIP & + ) and Late Jan 2013 for Auris.

It is possible if a repair was completed before the dates above that the a modified manifold was fitted but that it is not the latest part # 17201-37054 that was introduced at the dates above and has had 5 version ending -37050/51/52/53.

2. For noises occurring at temperatures below -10 degrees C which involves fitting modified injectors and updating the software the fix dates for production varies by model:

Prius dec 2011

Prius PI May 2012

Prius + March 2012

Auris MK1 Dec 2011

Auris Mk2 Start of production.

As the weather has been very cold recently you may be experiencing issue 2 as well as issue 1 if an earlier manifold type was fitted.

[grahamh]

Thanks Lee

Very Helpful

[grahamh]

Hi update,

Car been into garage later modified manifold as been fitted.

Hope it is sorted.

[Grumpy Cabbie]

It should be.

Still possible to get a few cold nights in Feb, so plenty of opportunity to find out. Glad it's all sorted.

[kevin h]

Good god, cant beleive this is srill happening. Toyota shoyld have sorted this out years ago.

[grahamh]

It Seems if you thought it was fixed earlier it was not ,you would have thought Toyota would have contacted owners of the Prius cars that had the 1st modified manifold fitted ,to advise them that a later version was available.

Will check it out in the next days.

Ok if you let it warm up before you switch it off after a cold start it may not happen ,Prius was engineered for economy ,not to waste fuel warming up a cold engine.

Only thing bothers me is the damage explosions do in the exhaust ,a Catalytic converter may be damaged and looking at it, it does not look cheap!

[johalareewi]

Had this last week (first time ever).

Moved car about 100 yards at lunchtime (the ICE fired up).

Went to start car in the evening and got the lumpy engine.

[grahamh]

I think all the early Gen 3 suffer from this fault.

Mine was under warranty just, runs out in June 2015

[Grumpy Cabbie]

Isn't it also partly software? I believe there are a number of different versions out there and varieties thereof. This became apparent on the US Priuschat forum when the inverter recalls were in full swing. Some owners experienced severe retardation of acceleration following the recall and others didn't. Upon investigation it turns out there were different software versions in use, some allowing harsher use of the inverter.

Once updated to the latest versions throughout, owners have had happy cars that start fine on cold damp mornings. Well, so long as they got the updated manifold aswell.

[Chris Dance]

Our dealer changed the manifold on our previous Prius which cured the problem. The dealer stated that if the manifold change did not fix it they would change the injectors. (After the manifold change the car was fine.)

[grahamh]

Hi Grumpy

I thought my first manifold change was for a modified one ,but now I have an other modified one thought it would have been cured 1st time!

Will have to check over next few days.

[Drpepper99uk]

Hi everyone,

My car has experianced similier issues today(with a difference), I started it up all was fine. Drive to the zoo as was taking the kids out for a stomp around and along the journey some 20 minutes in I could feel the car jolting slightly and didn't think anymore about it as we were doing 70mph along a motorway. I got to where we needed to be, and upon pulling up the engine was making a funny clanking noise and I noticed that there was no indication on the display of any EML light and also no arrows showing up on the charging system indicating engine or electric motor charging status despite the engine running once I stopped which I thought was strange as usually with a full Battery it will revert to EV drive mode and silence upon stopping after a long journey.

After the visit, I got back into the car, started it and it made the clanking noise again and on the way back I could feel the car jolting worser still although it still drove and got us all home luckily-no lights on the dash still!! Is this modified manifold part related to not just startup noises but also jolting? I have no idea if my car has ever had the modified part fitted and i'm trying to rule out if I need to have the modified manifold fitted to stop the tell-tale noise upon startup as everyone has explained in this thread, but also maybe the injectors looked at which would be where the jolting problem stems from or does the older manifold part cause driveability issues as well?

I have a 59 plate Prius, way outside of any free repair period I guess. How can I get Toyota to check if my car has been modified with the TSB info and part required? And failing that, how much is a replacement manifold?

Mike.