1KR-FE engine rattle noise under load

[volodymyr]

Hello everyone,

I am currently an owner of tiny Peugeot 107 which is equipped with Toyota built 1KR-FE engine.

The problem I am experiencing is some rattling of the engine under load when accelerating the car on 5th gear. This does not happen on neutral, so I can't really test it with opened hood in a stationary position.

In order to illustrate the noise I have recorded an audio using the phone from inside the car when driving. It is a very bad quality, but it actually allows you to hear the noise and probably have some clue about it.

It typically happens on 5th gear when accelerating under load. For example, you are driving on 5th gear and you need to accelerate, you press on pedal, and this sound is produced. If you remove the foot from pedal, the sound is gone immediately.

The sound file can be found here: https://soundcloud.com/user641485394/enginerattlenoise

Starting from 48th second of the audio you start to hear the sound. On 54th second I remove the foot from the pedal and it's gone. On 59th second I press on gaz again and the sound is stronger. The strongest sound can be heard starting from 01:07.

Any idea where this it may come from?

Thanks!

 

[Brent_G]

What RPM does this happen at and how much throttle are you giving it? It could be simply you are lugging the engine to much and getting some preignition.

 

[volodymyr]

Brent_G,

Originally Posted By: Brent_G
What RPM does this happen at and how much throttle are you giving it? It could be simply you are lugging the engine to much and getting some preignition.


Thanks for a quick reply. In fact, the car is so simple that it is not equipped with the tachometer

so I can't really know what the rpm is.

It is a semi-automatic transmission, so it is up to ECU how to mix the fuel/air and what ignition to set ...

It usually happens on a 5th gear when accelerating no matter what is rpm, I think.

 

[Quest]

5th gear acceleration?

What speed were you in when accelerating from 5th gear?

I suspect that you may be lugging your engine. Try downshifting to 4th gear and see if that helps?

Q.

 

[volodymyr]

Quest,

Originally Posted By: Quest
5th gear acceleration?

What speed were you in when accelerating from 5th gear?

I suspect that you may be lugging your engine. Try downshifting to 4th gear and see if that helps?

Q.


In this particular case I was doing 95 km/h accelerating to 100 km/h. It is quite common to hear this sound when accelerating from 100 km/h until 110 for example.

Since car is switching gears on it's own (it is a robotized manual transmission) I suspect that it should work fine when it is in "automatic" mode. I.e., it is up to ECU to determine the load and switch to 4th or stay at 5th.

If I switch to 4th, the sound is usually almost gone. If I switch to 3rd, the sound will for sure be gone, but doing 3rd gear at 100 km/h is bad I think.

 

[Danno]

Try a higher/highest octane of gas and see if that helps.

 

[volodymyr]

Danno,

Originally Posted By: Danno
Try a higher/highest octane of gas and see if that helps.


Thanks for the reply. When I noticed this problem, I actually did try a higher octane gas: I normally use 95, but I tried 98 and it changed nothing.

I will try this again but using some well-known gas station like Shell or Agip, since I normally use an local noname gas station which is close to me.

 

[Trav]

Any check engine light?

 

[volodymyr]

Trav,

Originally Posted By: Trav
Any check engine light?


Nope. If that would be the case, it would be a totally different story: I would go for a dealer to hook-up OBD scanner and see what's wrong.

 

[Trav]

It does sound like pinging as others have posted. i would be curious of how much the timing is being retarded and the knock sensor operation.

Check for a small vacuum hose being off somewhere then try premium fuel from another station as you said.
Look at the fuel trim to see if its running slightly lean and then the EGR passages.
A decent scan tool should get to the bottom of this if its anything other than fuel.

 

[19jacobob93]

Deffinitely pinging/predetonation
I imagine such a tiny engine has virtually zero torque in 5th gear as all the power would be in the latter half of the rpm range. I wouldn't try and accelerate 5th anymore as it can be very damaging to to the engine when it starts pinging.
What you said about it going away in 3rd or 4th confirms this so yeah drop down a gear or two to utilise the revs and you'll be fine!

 

[volodymyr]

19jacobob93,

Originally Posted By: 19jacobob93


Deffinitely pinging/predetonation

[...]

What you said about it going away in 3rd or 4th confirms this so yeah drop down a gear or two to utilise the revs and you'll be fine!

Well, the problem is that my wife uses the car only in "automatic mode", and it's up to "robotized gearbox" to decide which gear to use. Sometimes it uses 5th gear even at small rpms.

If this is predetonation, I wonder, can I minimize the effect by simply changing the knock sensor? Somehow I think that Toyota engineers should have thought that when this engine is used with semi-automatic transmissions it can actually be at low rpm but at high gear (5th of 4th), so detonation sensor should catch that. Right?

 

[volodymyr]

Trav,

Originally Posted By: Trav
It does sound like pinging as others have posted. i would be curious of how much the timing is being retarded and the knock sensor operation.

Check for a small vacuum hose being off somewhere then try premium fuel from another station as you said.
Look at the fuel trim to see if its running slightly lean and then the EGR passages.
A decent scan tool should get to the bottom of this if its anything other than fuel.



Thanks. I will check the hoses, but given the price of knock sensor (50 dollars) I think I can simply buy a new one and try it out.

 

[Trav]

I would expect a P0325 code if it were bad though, thats was why i asked about the CEL.
If the knock sensor and fuel doesn't do it i would suspect a slightly lean condition.
Other than hoses or something obvious a scan tool is best at diagnosing the condition.

 

[volodymyr]

Originally Posted By: Trav
I would expect a P0325 code if it were bad though, thats was why i asked about the CEL.
If the knock sensor and fuel doesn't do it i would suspect a slightly lean condition.
Other than hoses or something obvious a scan tool is best at diagnosing the condition.


I guess if some hose is off, I would have an unstable idle, which is not the case. I will check it for sure. Check engine light has never been seen on this car since I bought it, I guess it means my situation is not that bad ...

 

[19jacobob93]

My car (the Ford) does the same and that is an auto, mainly if I use 91 octane and the problem goes away with 98.
But say i'm in 4th and the engine is turning over around 900rpm and i try accelerate lightly it will start pinging (when using 91) but if i put my foot down a bit more and it changes into 3rd, it will lift to about 1500rpm and the pinging goes away because the engine is no longer laboring.
I don't think anything is faulty on the car, but it's just a case of the timing being slightly out because the engine isn't opperating in a suitable power band for the driving situation. In which case it's in your hands to change that by putting your foot down to shift down in an auto or change to a lower gear in a manual.

It's like in a manual car when you go to set off in a rush and let off the clutch too quickly, it nearly stalls but doesn't, just shudders and makes that rattling sound which is often the engine pinging since the timing is thrown out for a second or two as the engine labors

 

[volodymyr]

Thanks for all your comments. I will try to use Shell v-power (100 RON) and see if this changes anything.

It might take a lot of time for me to use the old gasoline which is currently in the tank until I will be able to try higher octane.

So you will not hear from me for a while

 

[Olas]

I suspect a fault in the shift map or shift logic. It really should change before it starts to ping. Is the knock sensor ok? Crank/cam position sensors? I struggle to believe they would be so lax on QC and NVH.
Maybe customer expectations are different over there

 

[volodymyr]

I just checked if all visible hoses are okay and noticed that one of them is loose. I did a picture of it: (high quality image, therefore it may take a few seconds to download):

https://dl.dropboxusercontent.com/u/17030088/20141008_225839.jpg

As you can see in the middle of the image there is a tube marked with yellow line and it looks like the hose is cut by a metal clamp. This does not look okay. If I touch it, it feels kinda loose.

I wonder can this loose hose cause the sound I have?

 

[Trav]

Is it cut through? If its loose either put another clamp on it or change it, loose or damaged hoses are never a good thing. Where is this hose going?