XSeries-forum

Any suggestions guys? Driving back from Cornwall. Started to hear noise from engine, so pulled over and heard horrible noise coming from engine. Didn't loose any power that I remember. It isn't misfiring and no warnings on display. Injectors and crankcase breather we changed / serviced under 5k ago. Car is on 120k now. One thing I have noticed is that if you run engine with oil cap off the is a lot of pressure coming out, is this normal? I fear the worst.

checked oil level??,  checked cracked exhaust manifold??

couple of places to start

Before getting too deep into the engine have a very close look at the front crankshaft pulley these can knock like hell when the rubber inner damper fails . If the engine runs sweet I would have a close look here first they make a surprisingly bad noise not unlike a big end knock.
Good luck hope its simple

Oil level is ok. Had new exhaust manifold so that's ok. Will have a look at the pulley? It does sound broken. Lol

I assume we're talking about this little device?

Yep that's the one.

I know it sounds a long shot but seen this more than once.

Crank pulley ok. Think it might be timing chain. Oh well need to strip it down and have a look.

Update. Removed inlet manifold, injectors and rocker cover today. Found number 3 injector soaking wet with diesel compared to others so they are going off to be tested. I'm just hoping its not bent a rod on the process. On the bright side everything else looks fine.

Might be an idea to do a compression test whilst they are out??
Will give you a little more info on the internals??

I may well do compression check but just going to wait for injector results before next step. Hopefully sometime early this week all being well

Sounds like it could just be an injector fault as they can cause rough running at idle. If you can read fault codes that would help. 

Not trying to state the obvious but make sure you put the correct injector back into its corresponding  cylinder as each one is individually coded to the car.

Hope it is a cheap fix for you mate, and yes one faulty injector will cause a rough idle which would be logged as a fault in the ECU.


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Injectors all marked so will go back in same order. No codes were stored. Just waiting to here from injector place now

Injectors all came back ok so have now removed the cylinder head. Piston number one can be moved up and down by hand at least 4/5mm so that is the problem now just got to remove sump to find the cause. Either big or little end bearings failed i suspect, hopefully crank should be ok. Very pleased to find the problem though.

Thats not good news, if you can move the piston that far I would reckon its the bottom end rather than a little end. I have had 2 bottom end failures recently, once on the X5 which damaged the crank, and once on my Ducati which didnt (the bottom end bolts had come loose). Hopefully you will have caught it in time and the crank will be OK