Disco 4 (LR4) P1247 low boost pressure

Over 200k miles now. Previously had secondary turbo actuator faults, ‘fixed’ with replacement diverter valve and poking at the secondary turbo actuator itself (last year).

Now has a pronounced hiss on acceleration that sounds like it’s from the air vents, smell of exhaust gas in cabin, some exhaust visible seeping from back of engine on start-up.

With this is an occasional restricted performance condition. Nothing picked up by GAPIID, but oddly the Foxwell NT680 shows P1247-00 low boost pressure.

I assume this is a leaking EGR crossover pipe, and a body off job. Could anyone confirm this/suggest anything else?
Cheers

Manifolds split on the 3.0, apparently smoke machine is best way to locate said split.

As said most commonly a cracked inlet manifold very common fault get it smoke tested

Thanks, I’ll give that a try. Do you think the exhaust gas smell could be coming via the EGR then?

RH EGR pipe rots away resulting in exhaust gases in the cabin. Ask me how I know?

Lazydave said:

RH EGR pipe rots away resulting in exhaust gases in the cabin. Ask me how I know?
View attachment 265736

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I saw your pic on the Disco3 forum. Can you get to the pipe with body on, and if so, how?

guineafowl21 said:

I saw your pic on the Disco3 forum. Can you get to the pipe with body on, and if so, how?

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Someone on that forum said they did it on the drive and took 2 days. I stripped mine down twice but could not see how to access the bolts. Decided to give to my local Indie. However a bolt snapped which resulted in body off.
I could see under the rh wheelarch exhaust gases if someone gradually increased the revs. I sprayed water on the pipe which you could see bubbling.

Lazydave said:

Someone on that forum said they did it on the drive and took 2 days. I stripped mine down twice but could not see how to access the bolts. Decided to give to my local Indie. However a bolt snapped which resulted in body off.
I could see under the rh wheelarch exhaust gases if someone gradually increased the revs. I sprayed water on the pipe which you could see bubbling.

Click to expand...

Sounds wonderful.

Did you get hissing on acceleration/boost leak messages?

Occasional restricted performance, usually on light throttle and hissing which sounded to be from your feet area or behind dash. The pipe has some heat protection on and a clip at one end (under the car). It is where the clip is that they rot. Usually pin holes. I towed our caravan for 3 hours all OK. Unhooked it pulled off and got restricted performance. Turn off for 5 minutes and all was good again.

Thanks. I’ll look forward to that at the weekend.

I had this problem with the blowing egr pipe. I managed to change it myself but be prepared to question why you got a discovery. Access to the bottom bolts via the wheel arch and removing the heat sheild. Top bolts access I took out the air box and tray behind it. I used a flexi bit holder in the impact driver, various extensions on the mini ratchet, maintenance spray and a blowtorch. One of the bottom bolts was seized but removed with some heat from the blowtorch. Putting the new pipe in I got the top back bolt as tight as I could while still able to move the pipe to fit the bottom bolts as the top bolts are offset and access is difficult so you only want the minimum to tighten. I enjoy trying to fix things on cars but this job tested my patience......hope this helps and good luck

Lazydave said:

Someone on that forum said they did it on the drive and took 2 days. I stripped mine down twice but could not see how to access the bolts. Decided to give to my local Indie. However a bolt snapped which resulted in body off.
I could see under the rh wheelarch exhaust gases if someone gradually increased the revs. I sprayed water on the pipe which you could see bubbling.

Click to expand...

Hi. I know this is an old thread but I'm having similar issues. Just wondered what the body off work cost at your indy? Thanks