P38- V8 DOWNPIPES/CATS/Manifolds

MY2000 4.0 ( THOR ) V8 HSE with 72000 miles: Have a 'tinny' clattering noise/ rattle coming from front of exhaust system when engine running - seems to be louder underneath but see no blow-out anywhere. Also strong exhaust fumes in cabin when window is opened whilst driving. Are cats buggered or would problem be manifold or gaskets ? ( From downpipes back is newish stainless steel system )

Seen an ad on ebay for front pipes/cats, and noted that up to MY '99 replacements are £150 but for MY2000 -02 replacements are £250 !! Are these pipes not identical for all P38 V8's ????

My RR has done about 4,000 miles after an engine rebuild. When first started ( after being laid up for 2 years ) I discovered both cats were glowing red and engine dropped off cylinders then stopped. Discovered centre box was blocked with crap/nuts - courtesy of a squirrel or similar !! New box fitted and recently this tinny noise has appeared otherwise my RR driving fine except for steering wander /bump steer

If its at the front it may wellbe the manifold blowing , would explain the smell . Although it must be quite a blow to get fumes in the cabin .

Sounds like cats, only diff i can think of is sensor position? or number of?

Have you tried universal cats , you need to weld them in and get the correct bore . CES did do them about a year ago , got them on my rrc LSE

If its the RH manifold blowing - can this be welded or do the crack at expansion /accordian section ?

either manifold can be welded , Land Rover fitted mild steel manifolds to the p38 , unlike the classic , bloody cast iron .

I think the difference between pre 99 and post 99 cats are the number of sensors, 2 for pre 99 and 4 for post 99 and also the thread size of the sensors. Also post 99 cars cats should be type approved with the correct stamp on them that says they have type approval.

elsie said:

either manifold can be welded , Land Rover fitted mild steel manifolds to the p38 , unlike the classic , bloody cast iron .

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You sure? I thought they were stainless and therefore very difficult to weld.

I've got a similar problem with mine - clatters like buggery - but I'm pretty sure the previous owner emptied the cats when they started to break up and that's where the noise is coming from. They've been on my list to replace since I bought it but other things won't stop breaking.

Originally I had a garage tell me it was a cracked manifold, but I've concluded it isn't.

I get an occasional whiff of gas via the sunroof but not the windows. Quite strange.

post 99my only have 2 co2 sensors (before cats)yanks got the 4

kooky_guy said:

You sure? I thought they were stainless and therefore very difficult to weld.

I've got a similar problem with mine - clatters like buggery - but I'm pretty sure the previous owner emptied the cats when they started to break up and that's where the noise is coming from. They've been on my list to replace since I bought it but other things won't stop breaking.

Originally I had a garage tell me it was a cracked manifold, but I've concluded it isn't.

I get an occasional whiff of gas via the sunroof but not the windows. Quite strange.

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They are stainless,but weld very nicely with mild steel wire in a mig welder - done loads. Not worth setting my Tig up,too slow.....