TD4 Engine Smoking and Knocking!

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andyfreelandy

Well-Known Member
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5,155
Location
Devon
Read the threads on similar, but need a steer please before spending money as this seems different !

2002 TD4 - 102k miles. All well and serviced regularly including breather filter.

Last week, one morning it refused to fire. No fault codes. After leaving it for a day it started and runs.

Used it today - white smoke when turbo comes in. Short journey home white smoke at tickover.

When gently revved up knocking, not sure where from exactly. Maybe engine, maybe turbo.

Rather scarily it then refused to stop when I turned of the ignition key !

Having read a few disaster threads, I stalled it immediately.

Not wishing to completely stuff the engine - what to do next please??

Thinking so far - white smoke is unburnt diesel - maybe injector.
Running on is maybe engine oil through turbo.

But both together - on the same day?? also - failing to start must be linked and that is not turbo - so change injector(s) and try again - but why the knocking and why the running on?

Many thanks. Andrew
 
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No posts - no one has had a similar problem???

Anyway - update. Car recovered to nearby auto centre. Described problem and they agree severe over fueling.

so - they will be testing injectors tomorrow and seeing what results are.

I tried the car before leaving it with the garage to show that it ticked over fine and smoked white. Hope it is only an injector or two.

Apparently turbo would be black smoke and fuel filter would not give such a dramatic effect.

Comments / corrections please???
 
Sounds like an injector over fueling or a miss timed fueling as has happened to a friend of mine with his van it turned out to be an injector an a cam or crank senser can't remember which one but the knock came from the miss timed injector.
 
You did right by stalling it , avoiding a runaway , when a turbo blows it's white smoke first , if the engine is not stopped by stalling , it's black smoke second , as the engine oil is burnt as fuel , and thirdly sparks as the engine seizes :eek: hope its just a injector problem !
 
O.K quick update.

Transportered to nearby garage who seemed to understand fault.

They have now had it for over a week. Replaced 2 'faulty' injectors and they called yesterday to say it is £600 including parts but the car is just the same as it was when it came in.

Not impressed !

I suggested to them when I took it in that it was a fairly 'catastrophic' failure and they observed diesel in the oil in large volumes. I also suggested the high pressure pump leaking into oil - anyone had this?? They said the car wouldn't run if it was this.

They now want to change the HP pump ! Another £400 plus labour.

Me thinks we are going to have an interesting discussion in incorrect diagnosis and costs associated with it. Watch this space !

Anyone else had an HP pump fill up their sump?? Cheers
 
O.K quick update.

Transportered to nearby garage who seemed to understand fault.

They have now had it for over a week. Replaced 2 'faulty' injectors and they called yesterday to say it is £600 including parts but the car is just the same as it was when it came in.

Not impressed !

I suggested to them when I took it in that it was a fairly 'catastrophic' failure and they observed diesel in the oil in large volumes. I also suggested the high pressure pump leaking into oil - anyone had this?? They said the car wouldn't run if it was this.

They now want to change the HP pump ! Another £400 plus labour.

Me thinks we are going to have an interesting discussion in incorrect diagnosis and costs associated with it. Watch this space !

Anyone else had an HP pump fill up their sump?? Cheers

What else can you say other than take it to a garage who know what they are doing rather than one who which does not and will mess about and p*ss away your money trying to diagnose by swapping expensive parts rather than science. Would also suggest you let them make up their own mind rather than giving them ideas which they can then use as a reason to charge you for replacing parts which may have been okay.

I would suggest that the problem could be the fuel pressure regulator on the back of the HP pump. Symptoms that point to this diagnosis are - based on the assumption that there is only one problem:

- Failure to start (no fuel pressure)
- Failure to stop when key removed (the engine stop on a TD4 is controlled by the fuel pressure regulator) (but it should still stop after approx 4-5 seconds as the LP pump is de-powered)
- Over fuelling

FYI when a turbo oil seal fails it can go in two ways - if it is leaking into the intake tract you get blue/white smoke and it can cause the car to "self fuel" which can result in engine destruction if it causes it to over rev. If it is leaking into the exhaust tract you get white smoke of oil vaporising and the engine cannot self fuel as the leak is downwards of the engine.

To my knowledge a faulty HP pump would not cause diesel to get into the oil in large quantities. it is lubricated by the diesel itself. It could be you have a holed piston or broken piston rings?

I would suggest next steps are

- Compression test of all cylinders
- Fuel pressure function test.

For the latter there is a thread on here on how to do it with a inexpensive kit from Machine Mart.

Good luck...
 
Thanks Tannaton, very useful diagnostic info.

Certainly will not support any more changed items without conclusive diagnosis.

Is the regulator part of the pump?

Certainly sounds a possibility and will see if they can do a test, would have thought the pressure fault would show on diagnostics??

Andrew
 
Thanks Tannaton, very useful diagnostic info.

Certainly will not support any more changed items without conclusive diagnosis.

Is the regulator part of the pump?

Certainly sounds a possibility and will see if they can do a test, would have thought the pressure fault would show on diagnostics??

Andrew

The regulator is viewed by some as part of the pump as it is integral to it but it can be changed separately and is easy to remove.
 
Quick update.

High Pressure Pump removed and signs of leak at pulley end. Believed to be spraying diesel vapour (at high pressure) into crankcase. Hence the running on.

However, still smoking when warm, this may be residual fuel in exhaust?

Going to run it for a while and see if it clears.

It would appear that this failure is not very common but will defo confirm the end result for future reference.

Thanks for all the ideas and info.

Andrew
 
Quick update.

High Pressure Pump removed and signs of leak at pulley end. Believed to be spraying diesel vapour (at high pressure) into crankcase. Hence the running on.

However, still smoking when warm, this may be residual fuel in exhaust?

Going to run it for a while and see if it clears.

It would appear that this failure is not very common but will defo confirm the end result for future reference.

Thanks for all the ideas and info.

Andrew

Andrew I'm struggling to make sense of this - the high pressure pump has three connections - there is diesel in from the tank, high pressure diesel to the fuel rail and low pressure diesel return to the tank. I can't see how a leak from the pulley shaft could cause diesel to enter the engine block?

Clearly from what you say it has made some improvement, and yes oily deposits could have gathered in the exhaust and CAT, but I can't see how that would have happened from a diesel leak?

Hope it's sorted for you, sounds like it's cost a lot of money, let us know?
 
Thanks for the thoughts.

I couldn't work it out and thought that the diesel from the pump shaft was going into the oil and then causing the run on, but having thought about it I think high pressure fuel (atomised) was being sprayed into the crank case and probably picked up from the breather??

Only a theory but seems likely.

Will, of course, update the thread when the bank account is empty!

Seems odd that no one else has had this, most faults that I have had have been listed before - sort of pathfinder on this one - at my expense - oh well. That is what the site is about. Car is worth it otherwise it would have been curtains. AND if the injectors were also a bit iffy then that may repay me in fuel saved?

Have asked for old pump for inspection. Like to close these things out.
 
Promised close out - thanks for all the suggestions.

so - 2 injectors changed and problem remained. Largely un-surprised by this as I told the garage it was 'catastrophic' - one minute car went perfectly, next clouds of white smoke.

So - change of high pressure pump revealed seal at pulley end was squirting very high pressure diesel into timing chain cover and likely getting inhaled by crankcase ventilation. Car was then very happy to run for ever on this source of gasses!! yum yum.

Changed high pressure pump (complete with regulator) so won't be able to confirm whether that was also faulty, and after a couple of days of exhaust smoke when hot (residual unburnt fuel) all is well and TD4 is once again a happy engine.

So - if your car goes from running well to blowing like a train, inspect high pressure pump for leaks internal to the crankcase. O.K I am sure that the injectors were not perfect, but they were not the cause in this case.

Garage came good and agreed that my diagnosis was better than theirs. To pacify me they didn't charge any labour for pump change and the whole job cost me the parts and 3 hours. They had the car for 2 weeks. All work has 12 month warranty. Good outcome I think. Plus we have another rare failure mode defined with some free tests (look at pump seal) and a repair.

Cheers, Andrew
 
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