I’ve now ruled it out being something I’m doing,

If the car has been left for a couple of days the pedal goes hard, so that you have to apply a fair bit of pressure to activate the brake switch and get the car to start. Once running it is all fine again. And if it’s turned off and only left overnight or for a few hours the pedal feels normal.

I know that pressing the pedal with the car off will firm it up but I’m not doing that, it’s firm when I get in. I put my foot on it and there is little give.

Does anyone have any decent thoughts on what may be causing this. My thinking is it’s bleeding off some servo vacuum pressure while it’s standing or something similar. Can’t see anything obvious. There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
Fiat 500x 1.4 multiair Lounge 2015
2010 LR D4 Commercial 2.7 TDV6

Done a bit of googling while waiting to have my hair cut.....

There is a non return valve on the servo? This could poss be bleeding back. Further investigation required.... There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
Fiat 500x 1.4 multiair Lounge 2015
2010 LR D4 Commercial 2.7 TDV6

Mine does that, now and again!
Watching with interest  2014 vogue se

LR046916

Ok so far I can’t see a separate NR valve on micro at, this is the number for the pipe from the air pump to the servo, if there isn’t a separate valve then it’s and 80-90 pipe rather than a £2 valve..... ing LR....

Busy until later so will have a look on the car in a bit and see what’s what.

This is best guess scenario at the moment. There may be a valve built into the end of the hose which can be pulled off. There isn’t much too them so a quick blow out might sort it... There is nothing that can't be fixed with a hammer😜😜
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2010 LR D4 Commercial 2.7 TDV6

Had a quick look and the pipe is an easy swap, there is an NRV in the end of it on the servo end, but this is part of the pipe!! It may be possible to pull it off and put in a non standard valve but this will be a bit of a bodge...... on the brakes.....which is not a brill idea... There is nothing that can't be fixed with a hammer😜😜
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Fiat 500x 1.4 multiair Lounge 2015
2010 LR D4 Commercial 2.7 TDV6

Yes, there is a Non Return Valve in the servo or possibly, somewhere along the vac pipe.
Its very likely to be exactly the same part as many LR and other manufacturers vehicles.

It's not unknown for them to leak, but not common.
It would give the symptoms you have and exaggerate the pedal creep, if you hold your foot on the brake pedal as the engine starts & settles to idle

Easy enough to change if its in the servo & you can get your hand in to hold it and wriggle it out of the rubber grommet in the servo, then extract carefully from the vacuum pipe.
Be careful fitting the replacement into the servo. Do not push the rubber grommet into the servo !!
You can use eg washing up liquid as a lubricant to help it slide in.
If you push the grommet into the servo, the servo is effectively scrap, because the grommet can prevent full stroke of the brakes as it moves around inside (I know from experience examining "failed" returned parts when I worked for TRW !)

If it's in the vac pipe, there will be an adaptor in the servo which can be extracted as above, with the same "care" comments about re-fitting.
Warming the plastic pipe slightly might help in extracting the NRV from the pipe. Paul,
2001 Discovery 2 TD5, 211,000 miles & climbing
2006 FFRR TDV8 Vogue 151,000 miles & now sold
Member of Midland (Land) Rover Owners Club, www.mroc.co.uk

It’s one of those LR pipes which is shrunk onto the fitting, going to try and get it off the old one when it’s out and if I can find a replacement then I will do that, I have ordered a replacement pipe, which I will return if I can swap out the valve but if not will put the new pipe in.

The valve end itself looks pretty much like a standard banjo shaped NrV just that it looks glued/shrunk/solidly attached to the van pipe which is a more rigid plastic type rather than a rubber hose.

Servo end of the Pipe has something similar to this

Click image to enlarge

Have fitted the new vac pipe today, was about a 15min Job.

Basic info.

1. Bonnet in access mode
2. Remove engine cover
3. Disconnect the squeeze fitting off the vac pump (front left of the engine).
4. Unbolt the retaining clamp (8mm with ratchet and several extensions)
5. Remove next plastic clip from pipe.
6. Stand on a box and wiggle out the other end of the servo. It’s quite stiff and needs a good wiggle.
7. Unthread the old pipe noting the routing in relation to other pipes etc.
8. Thread in the new pipe.
9. Spray a little silicone lube onto your finger and rub it onto the grommet in the servo, spray a little onto the new NRV end of the pipe.
10 re connect the end to the vac pump. Redo the clips etc.

Will see if it sorts the problem. If not it can be ruled out as the cause... There is nothing that can't be fixed with a hammer😜😜
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Fiat 500x 1.4 multiair Lounge 2015
2010 LR D4 Commercial 2.7 TDV6

Watching with interest as I have a similar problem.

Part number for 4.4 TDV8 (RHD), as you rightly say, is LR046916 (which supersedes LR022954) - cost about £88
Part number for 3.6 TDV8 (RHD) is LR011529 - cost about £35

Makes me wonder why the cost difference. Surely they must be basically the same part, even if the precise shape of the pipe is different. Call me a cynic, but maybe owners of later cars able/willing to pay more? Current: 2010 Range Rover L322
Vogue SE, TDV8 3.6, Bournville
-----------------------------------
Now gone: 2002 Range Rover L322
Vogue, TD6, Giverney Green

Got a discount from local MD so was £72.  There is nothing that can't be fixed with a hammer😜😜
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2010 LR D4 Commercial 2.7 TDV6

NMJ - wondering whether replacing the vacuum hose on yours solved the occasional hard brake pedal problem you had/ If so, I am minded to try the replacement to attempt solving a similar problem on mine.

many thanks

Steve Current: 2010 Range Rover L322
Vogue SE, TDV8 3.6, Bournville
-----------------------------------
Now gone: 2002 Range Rover L322
Vogue, TD6, Giverney Green

unfortunately no.

Have been driving it relatively frequently so it hasn't really caused too much of an issue recently.

still got some narrowing down to do. Also changed the grommet and that didn't seem to make it any better either.

its got to be vacuum related though..... There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
Fiat 500x 1.4 multiair Lounge 2015
2010 LR D4 Commercial 2.7 TDV6

Hi NMJ.

Old thread but never ended in anything positive or a fix?.

Did you get to the bottom of it?.

I have the same rock hard pedal most mornings now....

Thank you. 2014 L405 3.0 V6 Autobiography Santorini Black 49k

Mine does it as well. I replaced the non return valve but it didn't fix it even though the old valve had a leak when I tested it on the bench. In hindsight I should have tested the new valve before fitting it. I just bough a generic part and joined it to the existing hose as even if you disconnect the hose after shutdown it should still hold vac. I suspect the servo is leaking internaly but I just live with it as it's only a slow leak and does not effect the brake pedal assistance when the engine is running and it holds vac during use in the day. 2012 TDV8 Vogue (L322)

Last edited by JayGee on 15th Feb 2024 11:02am. Edited 1 time in total

northernmonkeyjones wrote:

unfortunately no.

Have been driving it relatively frequently so it hasn't really caused too much of an issue recently.

still got some narrowing down to do. Also changed the grommet and that didn't seem to make it any better either.

its got to be vacuum related though.....