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Discussion Starter #1
Right, I am still trying to diagnose a problem with my P38 before I decide whether to spend out or move on.

Any help would be greatly appreciated.

When I go out to start the beast ('97 4.6) there is a god awful clattering noise coming from the front end.

It sounds like metal hitting metal and seems in tempo with the ehaust note / engine revs.

If I just leave it for about 20-30 seconds the noise goes away.
If I select 'drive' in the gearbox, the noise stays, and the bang changes spead as the engine revs do.

If I rev it slightly in 'park' or 'neutral' this seems to help a bit and the noise goes away quicker.

I have had a number of suggestions including

Flexi plate
Liners lifting in the engine
Exhaust manifold issues etc........

One RR specialst stated is sounds just like a flex plate whilst another suggests a new engine is needed?!?!?!?!

Has anyone had a similar problem / experience before I get really frustrated and bite the ebay bullet..............!?!?!?!
 

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1995-2002 Range Rover P38A
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RPM said:
It sounds like metal hitting metal and seems in tempo with the ehaust note / engine revs.
The above pointer is a give away but not being able to listen to the engine it could be flex plate but thats normally a tingling odd kind of noise

So I say.......
Valve related components.

If you get the repair done then make sure both rocker shafts, 16 rockers, 16 pushrods, 16 hydraulic lifters and valley gasket are done.

You didnt mention mileage and if any recent work was performed on the engine
 

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Discussion Starter #3
Hi there

No recent engine work. The noise has got progressively worse over the last 6-8 months.

144k on the clock at the moment.

It sounds like a very heavy bang clatter though, I'll try and film it.
 

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1995-2002 Range Rover P38A
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You need to determine if noise is internal or external of engine, a pice of pipe is a handy tool to help, place one end near your ear and then the other end you can use to go around the motor, be careful as the engine is turning and fingers are easily lost.

Flex plates are a known problem so listen down that end
 

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Discussion Starter #5
try this video

It only does it for a few seconds immediately after start up this time as its still warm from my journey home an hour or so ago.

But in normally makes the clatter for 10-20 seconds in a morning when cold



If i remember when I'm dragging the kids to school in the morning I'll take some video in daylight when it lasts longer..............!
 

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Hello,

I had the flex-plate broken and it sounded different.
However, It is easy to determine if the flex-plate is broken (but you need a friend to help you)

Get under the car and unscrew the small metal plate that is situated between the engine and the Bell-housing.
(It is moon-shaped)
Now you can see the fly-wheel and by turning the engine slowly, you will see 4 holes in the fly-wheel. (Use socket 24 or 27 on the crank-pulley).
These are used to fix the flex-plate to the torque-converter, with 4 bolts.
You will find out very easy if it is broken or not.

Hope this info helps you a little bit
Regards,
Alex
 

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Hello

To me your symptoms could be flexplate related but could be the reluctor ring on the fly wheel, if this ring cracks (an they do) it can hit the crank angle sensor and cause the ignition timing to go haywire, this in my experience causes a hard metallic banging/clattering, either check inside the transmission (as already suggested via the half moon shaped plate) or a quick check for debris via the round inspection cover/plate (3 bolts) or remove the crank angle sensor to check its not bend or been hit. I really hope it is not this otherwise either the engine or the transmission will have to be removed in order the replace the flywheel/reluctor ring (they are riveted together).

the reluctor ring has 35 teeth spaced evenly at 10 degree intervals with a gap (making up the 360 degrees) this gap is set IIRC at 20 degrees before top dead center any problem with the reluctor ring can cause the ecu to lose its track of the crank angle this can start as a slight miss in timing and develop very quickly into the most horrendous and alarming sound. the reluctor ring looks like a circular train track. i think cracks in the flexplate can cause vibrations and stress to this ring ultimately bringing about its failure it is a very poor design and one rover identified and changed,

Hope this helps either eliminate or confirm a few things.

ive got a photo of one i've removed
[attachment=0:1gc09swr]2006_061300017.jpg[/attachment:1gc09swr]
 

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2006-2009 Range Rover MkIII / L322
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I had a similar scary sound just a month ago. A quick poke about with a large pipe in the ear revealed a knackered rear alternator bearing making a loud 'clunking' sound at random intervals. New alternator fitted and all quiet again.

Hopefully yours will be equally as simple to fix.

Stu.
 

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YUP - that's the sound I also have right now!!!! it is DIY to change the Flexiplate - (just pull back the gearbox or?)


Also had it for som etime - very bad when it really cold outside - also getting a bit of judder in the steeringwheel.... - better get it fixed soon..... but no time -or money :crybaby2:
 

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Discussion Starter #11
Well she has gone in for her repair.

Managed to source a good 2nd hand flywheel assembley with flexplate and boss included.

The mechanic has started dismantling the necessary pieces to drop the gearbox to fully diagnose the problem.

Apparently one of the flex plate bolts was loose and after tightening it the knock was still present in some manner.

So I'll let you know how I get on as he makes progress.
 

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RPM said:
Well she has gone in for her repair.

Managed to source a good 2nd hand flywheel assembley with flexplate and boss included.

The mechanic has started dismantling the necessary pieces to drop the gearbox to fully diagnose the problem.

Apparently one of the flex plate bolts was loose and after tightening it the knock was still present in some manner.

So I'll let you know how I get on as he makes progress.
Make sure they also check the bigends! Easy job, just remove the sump and feel for play.
We had a 4.6 with 2 damaged bigends, loud banging noise, changing with engine load and temperature. They chewed up the crankshaft (expensive lesson regarding the importance of timely oil changes) and resulted in a broken flexplate as well.
 

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Discussion Starter #13
I'm pretty sure they will check all.

He is a former senior mechanic for a range rover dealer so knows his stuff.

Gonna have to change a rear air bag when I get it back as one failed just before I took is in for repair.

It's that bad I can hear the air escaping!!
 

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Discussion Starter #14
Well I got her back last week.

They have replaced the flex plate which nearly fell off as it came apart!!

The plate had cracked down all 4 bolt holes almost to the edge of the plate. I will take some photos soon.
The big holes in the flywhee. Were badly ovalised too so it's had a new flywheel too.
Fortunately none of the teeth on the ring plate were damaged so the sensor is ok too.

The gearbox is rattle free now and super smooth again.
Just need to sort the rear air bag now.

Thanks to all for your help diagnosing the problem. It would have cost me a fortune at a land rover mail stealer.
 

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Discussion Starter #16
Sounds very similar.....

Please get it looked at. I put mine off for ages and this is what it looked like when it came out













SHOCKING!!!!!!
 

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Discussion Starter #20
No I bottled it and paid a local specialist.

Advanced automotive near carcroft in doncaster.

Top job. Well happy.

Fixed my rear air bag at home though. With a little help from a friend.
Had to chisel the top part off where the pin goes through as it snapped when I pulled it!!!
 
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