So my tdv6 is off a pot, im thinking of unplugging the injectors one by one to find out which cylinder its on.
My mechanic reckons theres a valve not sealing because he can here compression noise in the inlet, so my question is what would cause this issue? im thinking damaged valve/seat, maybe a spring? im not too sure.
I know its a big shot in the dark but I really want to get as much info as possible before I go get the head removed, im nervous there might be damage to the piston/bore but theres no metallic type noise as far as i can tell, is there anything else i should be looking out for?

Any help greatly appreciated

Bump
Anyone? really at a loose end hear as its going to cost a fair whack in labour to have the head off and inspected and if it has damaged any pistons/bores im going to have to fork out even more, would really like to try narrow it down
Cheers.

The Manual wrote:

NOTE :
Each Injection event is controlled by a charge and discharge cycle allowing energy to dissipate in, and recover from, the injector. Never disconnect the wiring connector when the vehicle is running. The injector may remain open thus causing engine damage.

Cheers for the warning, can you shed any light on the rest of my issue?

Could be many things - injector, worn/damaged valve guides - best get a fault code reader on it. I assume it's not been owned by you since new, so previous issues/problems unknown.

Had it plugged in, only looked for fault codes though, should i be doing something more? for my seat/vw ive got software to run logs over different measuring blocks to determine exactly what different components are doing.
Is the land rover software able to do this or similar?
Only fault code it came back with i believe was l/h bank egr which i thought would cure it but unfortunately no change.

Read the codes it should tell you which cylinder is off, then swap that injector with another either from the engine and then see if the fault moves with the injector or replace if you have or can get hold of a spare, chech continuity in the injector harness, if these are ok then check compressions though you will probably not be able to remove the glow plugs to do this as they are well known for seizing and snapping but you never know !!

Good luck 2008 G4 RRSport TDV8 current
2009 TDCi 90 current
2018 Discovery 5 HSE lux current
1994 Dakar current

Cheers for the reply camelrock, ive heard about the glow plugs being stubborn so will the compression test be done by removing the injectors?
What are your thoughts regarding the valve(s)?

Only way to check the comps is by removing the glow plugs, as far as the valves go I don't know enough about these engines to comment, but I ' ve never heard of this before and I was on the Disco3 forum for 6 years though I'm sure someone with more nol will come along .. 2008 G4 RRSport TDV8 current
2009 TDCi 90 current
2018 Discovery 5 HSE lux current
1994 Dakar current

similarly ive never heard of a valve problem like it, my mechanic says the "wob wob wob" noise heard when the airbox is lifted is compression and if its heard in the inlet it must be a valve passing, ive only ever heard of or seen valves damaged when the timing belt fails so im stumped as to what it could be

its more than likely a bad injector, that is the most common cause of ruff running / loosing a cylinder.
i would suggest looking at the injector quantity using a suitable diag machine. then doing an injector leak back check and comparing the results. if the results are none conclusive then the next test would be cylinder balance test or dynamic compression test using a suitable oscilloscope.

if you would like any of these tests doing drop me a pm and i will be able to help.

regards

rich

If an inlet valve was stuck open, the plastic inlet manifold would have likely melted.

Compression test, or injectors out to be tested is your next step

you have pm rich

mikey, not sure what these engines are like, if the valves stuck open would it contact the piston or is there good clearance?
inlet is ok so would it maybe not be as serious as the valve been completely open but a bad valve seat or similar

Cheers for all replies guys, really appreciate it

replied mate

Disco_Mikey wrote:

If an inlet valve was stuck open, the plastic inlet manifold would have likely melted.

Compression test, or injectors out to be tested is your next step