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Discussion Starter · #1 ·
I've noticed in recent weeks thatthe engine runs on slightly after switching off the ignition, just like it is stalling before conking out. I've had a similar problem many years ago with a Sierra and was always told it was a carburettor issue. Obviously cannot be the issue here. Wondering if anyone knows what the issue might be and if I have to make another trip down to the dealer!
 

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If my memory serves me right, yours is a diesel?
It could be that the engine cut off in the fuel pump is not right. Diesels don't work like petrol engines in that they keep running unless you stop them. With petrol, stop the spark and the engine stops. The Sierra phenomenon was pre-ignition probably- this is something else entirely, even although it looks the same.
 

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Check your oil level now! if high change it as you might have some diesel in it! Usual syptoms for these engines, if it doesn't stop one day, select a gear quick, foot on brake and stop it that way, hopefully you haven't got an auto, because even i don't know how to stop one of them.
 

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Discussion Starter · #4 ·
Thanks for the quick response guys.
I've just checked the oil level, its fine although quite a black colour considering its 7 months old and 5k miles.

It looks like the petrol pump issue might be it, i will see how it goes, and if it persists will take it for its fifth revisit to its first home!
 

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colour is normal, in reply to a post i made on the honest john forum there is a fairly simple test for diesel contamination in oil (diy) i'll try to find it and post the link.
Edited by: Oldroverboy
 

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...or simply do your own using a piece of unwaxed white card. Let a drop of oil from the end of the dipstick fall onto a piece of card. Keep the piece of card suspended by the edges so that the part with the oil spot does not touch a surface. Leave the card in a horizontal position for twenty minutes or so.

Healthy oil should appear be translucent when held up to the light.

If it is opaque-and has a jagged edge then the oil is severely oxidised. This could be due to excessive heat, or due to the presence if glycol (antifreeze) which oxidises oil very quickly and is far more deleterious to oil than water.

Fuel dilution is manifested by light coloured halos around the main oil spot.

For diesel engines, you are mainly concerned by the ability of the oil to hold soot in suspension. If you see clumps of soot particles forming, then the oil is saturated with soot.

Use a card with a drop of new engine oil for comparison.

I keep regular checks and date them to monitor the deteriation of the oil. The results are interesting. After a long motorway journey (>200 miles) the oil always shows additional oxidation and the fuel dilution decreases markedly. During winter, with a diet of short journeys, the fuel dilution increases significantly.

It's a very old field test that is starting to be revisited.







This was one of the replies, works too!


Edited by: Oldroverboy
 

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Oldroverboy said:
Check your oil level now! if high change it as you might have some diesel in it!
Obviously it's good sense to check the oil level regularly in any car, even more so given the potential DPF-related issues with these engines.

Apologies if this is a daft question, though, but how is a high oil level related to the engine running on?
 

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Gaston, As I understand it the additional fuel used when in DPF cleansing mode is 'washed' into the sump oil, thus the oil can have have such a high level of fuel contamination that the engine will 'run on' using the diesel contained in the oil.
Aussie Ed
 

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Ah, OK. I knew about the issue of diesel getting into the sump, but not that this could cause running on. Thanks for the explanation.
 
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