Dedzep

New Member
Hi All!

I have been using this forum for years, Thanks to the Advice I have found here I have successfully replaced the Engine breather filter with the BMW cyclone one, Blanked off my EGR as well as a few other issues solved so Thanks!!

Now I have an engine problem! Recently there has been an engine knock, Usually when the engine is labouring, at first this was very intermittent and I didn't really take any notice (More concerned with the cracked rear Chassis!!)

Any way (And sorry for the long winded post Not helped by this apology!) Recently went on a 300 mile round trip and the knocking noise became more frequent eventually putting the Check engine lamp on and going into limp home mode (which I limped home nearly 150 miles! oops!!)

Got the old girl home and put my Carsoft 930 on and got a couple of faults, Cylinder balance control and Possible high pressure (not much help!) I cleared the codes and she ran fine most of this week
Today a very short journey (less than 2 miles I KNOW!) and I definitely heard the knocking noise again

I have searched all week and there are so many suspects I am confused and was hoping somebody had experienced similar etc and can point me in the right direction, I don't really fancy changing, Injectors/Sensors etc blindly read too many forums where people have spent 100's and still have faults
 
Suppose I should have mentioned, I am not experiencing any drastic change in fuel consumption No Smoke, No difficulties starting Only loss of power when Check engine lamp came on, Has been pulling like a train as well!
 
knocking sounds like lack of fuel at high throttle openings on one or more cylinders.

Its almost certainly not an airflow issue.

However its worth starting from a level playing field by checking all the air filter stuff and fuel filter stuff.
 
Wasn't sure this was relevant but was serviced only a few weeks ago Fuel filter and air filter were both changed I know the mechanic and these were 100% changed for Bosch units
 
Wasn't sure this was relevant but was serviced only a few weeks ago Fuel filter and air filter were both changed I know the mechanic and these were 100% changed for Bosch units

Good.

Now about those fault codes - possible hioh pressure? what does that mean.

Cylinder imbalance is suggestive of one or more injectors playing up..

Look I'm being armchair pundit here, but I am leaning towards an injector with muck in it or something.

Anyway to tell which cylinder is in trouble?
 
Well I did take off all the connectors from the Injectors 1 at a time, when I took off the connectors the engine began to miss I must admit I was hoping I wouldn't notice a difference on at least one of them but no. My Scanner doesn't tell me which cylinder is weak so i'm stabbing in the dark
It probably wont help but I'm going to whack a bunch of injector cleaner and some decent fuel in it and see how it goes, Main Stealer was less help than even I thought they would be
 
Well I did take off all the connectors from the Injectors 1 at a time, when I took off the connectors the engine began to miss I must admit I was hoping I wouldn't notice a difference on at least one of them but no. My Scanner doesn't tell me which cylinder is weak so i'm stabbing in the dark
It probably wont help but I'm going to whack a bunch of injector cleaner and some decent fuel in it and see how it goes, Main Stealer was less help than even I thought they would be

Cheap solutions that don't work don't cost a lot..:)

Mmm. I have just realised something. This is the older model with a second low pressure fuel pump under the bonnet?

I would check that somehow if possible - I think if the fuel pressure is low or fluctuating after that pump it needs replacing.

Also there is the high pressure injector pump and a well known problem - corroded connections to the fuel pressure sensors after that ..

Look I think that post the low pressure pumps there is only the high pressure pump, the sensors and the injectors themselves.

You are getting imbalance: I'd say that means is right at the injectors or the sensors.

The most vulnerable and cheapest bit seems to be the harness. so try that first off.





The fix is to replace the sensor AND the harness that connects to it.

I think I would find a good independent service agent that knows these engines with the gear to check all this out.

But as a first off look for the fuel pressure sensors and check for electrical corrosion

http://www.landyzone.co.uk/lz/f9/fuel-rail-pressure-sensor-harness-change-154473-2.html

seems to say that fitting a new harness is not too hard and the harness is cheap.

So again 'replace cheap items first' is the mantra!

The fuel sensor array is not so cheap ..
 
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Cheers it is the early model with the pump under the bonnet
I'll give all these jobs a go and see how things go
 
Hi All!

I have been using this forum for years, Thanks to the Advice I have found here I have successfully replaced the Engine breather filter with the BMW cyclone one, Blanked off my EGR as well as a few other issues solved so Thanks!!

Now I have an engine problem! Recently there has been an engine knock, Usually when the engine is labouring, at first this was very intermittent and I didn't really take any notice (More concerned with the cracked rear Chassis!!)

Any way (And sorry for the long winded post Not helped by this apology!) Recently went on a 300 mile round trip and the knocking noise became more frequent eventually putting the Check engine lamp on and going into limp home mode (which I limped home nearly 150 miles! oops!!)

Got the old girl home and put my Carsoft 930 on and got a couple of faults, Cylinder balance control and Possible high pressure (not much help!) I cleared the codes and she ran fine most of this week
Today a very short journey (less than 2 miles I KNOW!) and I definitely heard the knocking noise again

I have searched all week and there are so many suspects I am confused and was hoping somebody had experienced similar etc and can point me in the right direction, I don't really fancy changing, Injectors/Sensors etc blindly read too many forums where people have spent 100's and still have faults

hi

dont wish to step on anyone's shoes here but

was the car fine before do done the egr blank and crankcase filter

only reason I ask is when u put the egr bypass kit in , is it seated well onto the metal pipe with the 2 x jubilee clips on it, is the vacuum pipe properly capped off

have u checked that no vacuum pipes have comes off, disturbed any leak off pipes on the injectors

has the turbo filter been changed , has the arrow been put round the correct way, going towards the pipe

is there any leaks where the fuel filter etc has been changed

is the fuel system self venting, I've got the 2002 so Im not aware if they are or not

maybe the fuel pump is beginning to fail ???? , but I don't know the pre 2002 ones so take no notice, lol

hope u didn't mind me asking and don't wish to interfere it what others have said
 
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Thanks gstuart, The EGR and Crankcase were done some few months prior, HOWEVER now that you mention it there are 2 thing that come to mind 1 It has only started since the service so I will give the fuel filter a look 2) I did buy a lot of diesel from Morrison's (I don't usually)
Also I'm sure the noise from the ancillary pump under the bonnet has changed when I turn off the ignition Maybe nothing but I might change it just to be sure

I cleaned up all the wiring this weekend haven't done much with her so hopefully driving it around this week may show something
 
I did buy a lot of diesel from Morrison's (I don't usually)

I had occasion to drive a diesel car-transporter with one on, one towed, years ago. We filled up at an 'ultra cheap' diesel station. It barely ran. White smoke from exhaust, overtaken by a tank on a tank transporter going up a hill on the M1...after 150 miles filled up at a proper garage and all the symptoms disappeared.

More water than diesel?
 
ur very welcome

there has been on many occasions where supermarket fuel have caused problems

wonder if maybe getting some millars injector cleaner in it may help as it gives i think a few octane increase

i wonder what happended to all those poor drivers where one supermarket filled up the wrong fuels ??

hope u get it sorted out mate and it's just the case of this supermarket fuel

just wondered then as it started after the service if something has been left off, connection not put together properly ,

have a look at ur vacuum hoses and also the turbo filter is the correct way round ,

did they do all ur oils on the service, ie gearbox, diff, ird
 
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Well Here's a little more Replaced the sensor put in some good fuel and ran some injector cleaner through her. Things improved ever so slightly, However I Finally have an Error code of P0263 Which I think points to Cylinder 1 out of Balance I think I need to change this injector
Any tips for replacing them???
 
Injectors are expensive, if the symptoms are not too bad, I'd put a few more tanks of diesel cleaner through it - it could be sludge that got shifted into the system when the filter was changed.

Having said that, I know the TD4's have 'delicate' crank shafts that are prone to fracturing - does anyone know if running with an knock is likely to put undue stress on the crank?
 
it could possibly put stress on the crank have you a injector specialist near if so get it checked the pump under the bonnet is a low pressure one but could be full of rubbish and if stuck there are a devil to get out I ended up cutting down the side of the plastic on my early td4 as the in tank pump went I decided to change both and the filter as well.
 
In the end it was No. 1 Injector Came out a little easier than I thought, It was covered in some black sludge, A friend of mine had just broke an 05 Td4 so I swapped my Injector for one that was tested good and it seems to be much better! Going on a long journey this weekend so fingers crossed!!
 
In the end it was No. 1 Injector Came out a little easier than I thought, It was covered in some black sludge, A friend of mine had just broke an 05 Td4 so I swapped my Injector for one that was tested good and it seems to be much better! Going on a long journey this weekend so fingers crossed!!
Be interested to know how it goes
 
Injectors are expensive, if the symptoms are not too bad, I'd put a few more tanks of diesel cleaner through it - it could be sludge that got shifted into the system when the filter was changed.

Having said that, I know the TD4's have 'delicate' crank shafts that are prone to fracturing - does anyone know if running with an knock is likely to put undue stress on the crank?

Truth is the M47 engine is no worse on fracturing crankshafts than any other small diƩsel engine, what does go is the crankshaft damper
 
Be interested to know how it goes

that black sludge would have gone hard, as it would have been diesel leaking from the bottom of your injector make sure you have cleaned it all off and put a new seal on and make sure it is tight down, before it leaks again, I had it on my old one
 

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