citroen c4 1.6HDI - STOP low oil pressure light.

[Antoin]

Sisters car cut out on the dial carriageway today.
Oil level is fine so tried to start it and it just wouldn't catch.
Left it at that as didn't have any other tools to look at it.
Any ideas what it could be?

Thanks
Anton

 

[PeteMoore]

Low oil pressure

Or a duff pressure sensor

It won't start because it's probably trying to stop itself from grenading all over the road.

 

[Nicky]

Pull the sump off. I would be fairly certain the pickup pipe in the sump will be clogged.

Used to do 3 or 4 of these a week and they're easy to pull the sump off.

 

[Nicky]

An example of a clogged lift pipe;

A comparison shot with a new, clean pipe;

Asking the oil pump to lift through that is asking a lot from it. I'd the thoroughly cleaning the inside of the engine out, after removing the sump and ensuring that pipe is cleared, by means of several flushes and oil changes, replacing the lift pipe for a new unit.

 

[Antoin]

Cheers @Nicky Nick and @PeteMoore il get a look at it when I get it home tomorrow.

Unfortunately Charles Hurst have already butchered one of the bolt holes holding the sump on. Hoping taking it off again won't disturb it and cause a leak.

 

[Nicky]

There's around 24 bolts holding the sump on, and they're also bonded. 1 missing won't have a big impact on it.

A brand new lift pipe is around £35 all in from any Peugeot dealer, or else they can be had on eBay.

If you remove the sump and you are met by the above, I would recommend clearing the lift pipe, refit the sump, add 2 litres of oil and 2 litres of red diesel and allow the engine to run for 20 mins. Drain the sump, replace the oil filter, and repeat that. Once drained the second time, remove the sump and ensure all is clean, and then fit a new lift pipe.

When you're working at the car, also remove the large Allan key banjo bolt on the front of the engine which is the oil feed for the turbo. When you remove this bolt (you won't need to disturb anything else to do this), you will notice a filter in the centre of the banjo bolt. Use a pick or fine screwdriver to remove this small gauze in its entirety, then clean and refit the banjo bolt. It's recommended to replace the thick copper washers that sit either side of the pipe when removing and fitting these bolts. Again, they're readily available in any Peugeot dealer, and a pack of 4 is around £4 from memory. Have the part numbers wrote down in the toolbox as I ordered them that often, so will edit with them later.

 

[PeteMoore]

^^^ that.

Had to do it to ours.

Was able to put a new turbo (internals) fed pipe and pickup into the car for under £200

 

[Nicky]

^^^ that.

Had to do it to ours.

Was able to put a new turbo (internals) fed pipe and pickup into the car for under £200

Did you replace the vanes in the turbo too? The standard hollow vanes in them are atrocious.

 

[PeteMoore]

Did you replace the vanes in the turbo too? The standard hollow vanes in them are atrocious.

Compete core dude. Just swapped the housing over with the vanes and all still in it.

Surprisingly nippy wee car with the fresh stuff in it.

 

[Blackie]

As above really, common fault on these small French Diesel engines.

 

[Nicky]

As above really, common fault on these small French Diesel engines.

The DV6 is famed for this, and it comes down to the ridiculously long service intervals in such a heavily emissions based engine with a mere 4 litres of oil. The big problem is the fact that the sump bung is recessed into the sump pan, which means all of the spent contaminated oil can not be drained from the engine during an oil change. The last 4-500ml is left behind, and is of a sludge-like consistency. This is what clogs in the lift pipe and causes the problem above.

Another issue is the majority of mechanics and DIYers not pulling the oil filter out of its housing while the sump is draining. The filter on these has a nipple on the bottom which prevents the oil running out of the housing when the engine is stopped, to prevent dry starting. This also holds a large quantity (in relation to the low overall quantity of oil the engine holds) of spent oil which will mix with the new oil if not drained at the correct time.

Temperamental, hateful little bastid of an engine if not properly maintained, though it has to be be said that they are very frugal and easy run, if looked after, and easy worked on.

 

[Antoin]

Well got it sorted this morning.
Turned out to be a frayed aux belt which had ripped the plug off the crank sensor.
New belt and its running fine with no low oil lights.
I will however take the sump off and give it a clean out as I'm sure it's not in great Nick judging by comments on here.

 

[RCT]

Well got it sorted this morning.
Turned out to be a frayed aux belt which had ripped the plug off the crank sensor.
New belt and its running fine with no low oil lights.
I will however take the sump off and give it a clean out as I'm sure it's not in great Nick judging by comments on here.

Did you change the tensioners when you did the belt as normally they start to fail and then the belt frays?

 

[Antoin]

No tensioners on it @RCT it uses an elastic aux belt. Complete bollox of a job and has to be forced on. Sheite design.

 

[stevieturbo]

No tensioners on it @RCT Sheite design.

It's french lol