Td4 Rattle and stutter under load - SOLVED

Hi all,
Since the tail end of last summer, I've noticed an occasional metallic rattle coming from what sounded like under the car occasionally on longer drives when the engine is under load. When particularly bad the engine also stutters a bit in unison with the sound. It's become more noticeable the last few months, and after being unable to troubleshoot the problem despite checking these forums, ended up going to the Land Rover dealer to get an answer on what the sound is. I also get quite a bit of black smoke when the stuttering is at its worst, and when I put the foot down.

The dealer mechanic reckons I have a loose drive chain rattling against the cover, so that when it gets warm and particularly loose it has enough slack in it to cause small timing errors causing the engine to hiccup a bit. He didn't seem to be open to any other explanation.
'
Has anyone else experienced this with their Freelander?

Annoying as my car only has 110,000km (68,000 miles) on it, and the dealers quote to fix it here in Norway is 26,000 NOK - roughly £2,500!!!

(edit: changed the diagnosis from 'fact' to dealer opinion)

My first thing to do is put a decent injector cleaner through it. It sounds like injectors to me.
The timing wouldn't shift enough to upset the engine, even if the chain was flopping all over the place.
The timing chain system is pretty robust, especially at diesel engine speeds.

Nodge68 said:

My first thing to do is put a decent injector cleaner through it. It sounds like injectors to me.
The timing wouldn't shift enough to upset the engine, even if the chain was flopping all over the place.
The timing chain system is pretty robust, especially at diesel engine speeds.

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Hi Nodge, I read plenty of threads about this and did clean my injector contacts with WD40 as well as pour some injector cleaner in the diesel tank in case. However, would injectors only play up once the engine is warm? I would have thought that they would consistently cause this issue, but I never get issues until the engine is thoroughly warmed up.

It's also a really metallic sound which I don't an injector being able to produce... I initially though I had a loose plate in my catalytic converter. The landy mechanic insisted that a loose timing chain could cause the engine hiccups. He also admitted to never having done a timing chain replacement since it's not supposed to have issues though!

If the engine has had regular oil changes and good maintenance, you would be really unlucky to have a bad timing chain.
The original version of the M47 installed in bmw cars did have an issue but this was sorted out well before they were put in the Freelander and also remember the Freelander is detuned so less stress is put on it.
I would follow @Nodge68 advise and concentrate on the injectors first. A new injector loom and a really good dose of cleaner or have them refurbished.
And yes, injectors can make this noise.
Obviously, we can't say categorically that it's not your chain. But is highly unlikely.
Mike

The metallic sounds are diesel knock, probably because of fouled injectors. It's much more common to have injector issues than timing chain problems.

@Nodge68
Could the HPFP cause this issue when hot?
Mike

Skinny Mike said:

@Nodge68
Could the HPFP cause this issue when hot?
Mike

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It's always possible.
The live data while driving would need to be monitored to identify that.
When mine standard messing around after I got a dose of crap fuel. I was getting some quite alarming noises from the engine.
A few doses of injector cleaner and quality fuel has completely transformed the engine.

Nodge68 said:

It's always possible.
The live data while driving would need to be monitored to identify that.
When mine standard messing around after I got a dose of crap fuel. I was getting some quite alarming noises from the engine.
A few doses of injector cleaner and quality fuel has completely transformed the engine.

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Did you follow the instructions on the injector cleaner mix ratio or just pour loads in to speed up the cleaning process? Sorry for the nooby question, but I'm gonna try to see if I can get any joy out of injector cleaning prior to biting the bullet with the dealer service on the 29th (I've got 2.5 weeks basically).

NorseFreelander said:

Did you follow the instructions on the injector cleaner mix ratio or just pour loads in to speed up the cleaning process? Sorry for the nooby question, but I'm gonna try to see if I can get any joy out of injector cleaning prior to biting the bullet with the dealer service on the 29th (I've got 2.5 weeks basically).

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I always use injector cleaner as part of my monthly maintenance routine.
I have found that these BMW diesel engines are hyper fussy about the fuel they use. I always used to get fuel from a Jet station on my way home from work on a Friday night. However the station changed brands to some unknown budget fuel suppliers. I used one fill and suddenly all hell broke loose with the engine. It was coughing, chugging, dropping out and knocking like it was being hit with hammers.
So I put in a strong dose of Comma Diesel Magic along with a half fill of Shell diesel and the problem went away after 200 miles or so.
Since then I use only Shell V power and put monthly dose of Comma Diesel Magic, mixed with 1/2 a tank fuel. The engine runs much better now. Better than it ever has.

Thanks. I'll make sure to put some more cleaner in over the next weeks and fill with some quality fuel. If I see any improvement I'll be avoiding the dealer, but if not I'll let you know how that goes too!

If the problem really is the timing chain hitting the case - is it not simple enough to remove the case and look for scoring on the inside? Surely if it was hitting it, it would be in the same place each time and there would be distinct tell-tale groves.

I would also go for diesel knock - that would be my first choice. Agree with Nodge - sound like fuel issues.
Diesel knock is often heard when cold, but then when under load. Timing chain rattle is usually evident as idle NOT under load.
Fuel and injectors are the main culprits.
I think your mechanic is not very experienced and also ill informed.
How has the mechanic attempted to diagnose the problem ?

Have you checked the crank pulley? I had this type of noise and the rubber (in the pulley) fails allowing the outer and inner to rattle. Easy way to test for this is rev up engine in sunlight and look for metal particles (where the pulley is rubbing) coming up from the crank pulley with the draft from the engine. Also, you can loosen or dis the air con belt to reduce load on the pulley. This cleared the noise on mine but I then went ahead and concluded (incorrectly) that it was the air con pump pulley bearing ! It was worn, but not the cause of the noise. Similar to above, mine knocks under load with cheap diesel. I am doing sound level tests wit supermarket, normal and super diesel at 400 miles apart to see if the difference is measurable.

GrumpyGel said:

If the problem really is the timing chain hitting the case - is it not simple enough to remove the case and look for scoring on the inside? .

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No GG, getting access to the chain on a TD4 involves taking most of the engine to pieces and even then you can't really see inside.
It's a right bugger
Mike

Skinny Mike said:

No GG, getting access to the chain on a TD4 involves taking most of the engine to pieces and even then you can't really see inside.
It's a right bugger
Mike

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Hi Mike, what GG meant was the chain the L series used to tow TD4's when they break down......
tum te tum te tum..........

And, to prove that L series can have the very occasional - but easy to fix - problem - - - - here is an excellent demo of genuine diesel knock as a guide for anyone that hasn't really heard it.(this is caused by a failed 'commencement of injection solenoid' - a fairly common problem on the VP37 pump on an L series - yikes ! - yes, an L series) but is a good demo.
Unfortunately, I hear many like this driving around and the owner is oblivious to the fact that he has heavy diesel knock - his mates have told him 'they all do that' etc...

Make you cringe when he revs it..... anyone that hasn't heard diesel knock, now you have..

Joe_H said:

Hi Mike, what GG meant was the chain the L series used to tow TD4's when they break down......
tum te tum te tum..........

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Har Har, funny you , aren't you

Mike

Joe_H said:

Hi Mike, what GG meant was the chain the L series used to tow TD4's when they break down......
tum te tum te tum..........

And, to prove that L series can have the very occasional - but easy to fix - problem - - - - here is an excellent demo of genuine diesel knock as a guide for anyone that hasn't really heard it.(this is caused by a failed 'commencement of injection solenoid' - a fairly common problem on the VP37 pump on an L series - yikes ! - yes, an L series) but is a good demo.
Unfortunately, I hear many like this driving around and the owner is oblivious to the fact that he has heavy diesel knock - his mates have told him 'they all do that' etc...

Make you cringe when he revs it..... anyone that hasn't heard diesel knock, now you have..

Click to expand...

Thanks for the helpful video/audio. In short, the sound I get sounds NOTHING like diesel knock. It's a much higher pitched rattle type sound that has no distinct pattern to it. I got my wife to take a video while I was driving in an attempt to capture the sound a couple days ago - have a look! Hope this helps in case anyone is familiar with what could cause this particular sound. (edit: you'll have to turn up the volume a bit, there's a lot of background noise)

andyfreelandy said:

Have you checked the crank pulley? I had this type of noise and the rubber (in the pulley) fails allowing the outer and inner to rattle. Easy way to test for this is rev up engine in sunlight and look for metal particles (where the pulley is rubbing) coming up from the crank pulley with the draft from the engine. Also, you can loosen or dis the air con belt to reduce load on the pulley. This cleared the noise on mine but I then went ahead and concluded (incorrectly) that it was the air con pump pulley bearing ! It was worn, but not the cause of the noise. Similar to above, mine knocks under load with cheap diesel. I am doing sound level tests wit supermarket, normal and super diesel at 400 miles apart to see if the difference is measurable.

Click to expand...

No I haven't checked that, I'm not too familiar. Is it easy to check?

Joe_H said:

I would also go for diesel knock - that would be my first choice. Agree with Nodge - sound like fuel issues.
Diesel knock is often heard when cold, but then when under load. Timing chain rattle is usually evident as idle NOT under load.
Fuel and injectors are the main culprits.
I think your mechanic is not very experienced and also ill informed.
How has the mechanic attempted to diagnose the problem ?

Click to expand...

The mechanic revved the engine in the service bay, and diagnosed it based on the sound coming from around the right side of the engine.

I was quite critical of the quick diagnosis, so insisted that they sit with me while going for a drive to feel the engine hiccuping effect that shows up most of the time the sound comes. When they felt it they insisted that this could be caused by the engine timing falling slightly out of sync when the chain beats against the cover.

Did they look at the auxiliary drive belt and related bits. It does sound like something on there.
It's a tight space, but stand at the front of the car and look down the left side and you'll see the belt. Waggle whatever you can or stick a bar down and look for play. If you can, take the undertray off and look from below. The crank pulley is about 2inch diameter, alot smaller than the rest.
Mike