Citroen XM Forum

Being a bit creative with my expenditure this month I appear to need some or all of a 2.0i TCT
saloon exhaust including the cat. It's weird, it sounds noisy and leaking but prolonged prodding
about hasn't thrown anything obvious as leaking but the MOT man has failed it. On examining the
system the noise always seems to be somewhere else to where I look/feel along THE WHOLE
SYSTEM!?

Damned if I know but I don't have funds for a new cat, front, middle and back boxes when
it's hit and miss to determine what's making the noise! The middle box looks ok and the newest
yet has localised corrosion on the rear flange where it meets the middle rear box and appears to
be corroding along it's longitudinal seam weld. The bonkers square rear box looks quite rusty yet
seems the quietest!!

Anyone breaking/already scrapped a car I could buy a full run of 'part worn' exhaust from to tide
me over. It has to be TCT as boggo 2.0i won't work even though I have good new spares of these!

Andrew

Hi Andrew

Everything but the cat will fit from an N/A, my 20i is running a turbo exhaust from the cat back, its exactly the same its just the turbo cat has a different set in it to meet the turbo flange rather than the manifold, just thought it may make your search easier..........
i have spares but im not sure how good they are, i will check but im sure ive only got the back two boxes and not the full 3 plus cat.

D

That's interesting to know Dean - I was certain the diameters were different between the two.

I'm not sorted with the new boxes I have as they're n/a 2.0 NON CAT front box and I reckon the
middle cross box on the turbo is still model specific - heaven knows why it's so mad in shape
and size. But I may have a rear box that may work then - I'll need to look at them all closely...

If I was chucking a used system on to try and shake down where the noise is coming from I'd
ideally prefer a set that was together on a car already although beggers can't be choosers and
I'd be interested in anything that may be available!

All the best,
Andrew

i was sure the diameter would be different too and it is but only on the downpipe to the cat which on the turbo (and this puzzled me) is smaller
One other thing is ive never seen two systems the same which is even more of a pita, some are one piece from the cat through to the transverse rear box some are in two parts and some only have a cat + 2 sillencers some have a cat + 3 sillencers and early ones have the same combo but without the cat...........out of the 5 xm's ive had (4 N/A's and 1 turbo) all the systems have been different due to different makes of exhaust......this may well cause problems and so i wish you luck in getting what you want, ie a full system but i will photo and check what i have for you when i get to my store next week.
Why has it failed then? are you saying there are holes in every section or that the baffles have rusted out, if its the latter i dont think you can fail an mot for that or all stainless performance systems would be a fail....maybe its an "at the testers discretion" thing in which case you would be better off sacrificing a goat next time you take it in rather than doing a by the book pre mot check yourself

D

oh and have you tried the hand over the tailpipe trick?

Well this is it! Don't get me wrong, the current system is a bit rorty in it's sound and I'd expect
there to be a splt/blow or at the leat condensation dripping out and sooting up but I'm damned if I
can find anything wrong other than the obvious noise. I took it in for the MOT expecting an advisory
'exhaust system aged/deteriorating' due to missing baffles (or even cat innards as the emissions was
wavering about and borderline but passed) and I expected to crack out the MIG if the tester actually
pointed at something and said replace/fix "that" as to look at it's all solid and entirely silver (no rust
or splits) but all I got from him was there's noise so it's a fail. It's not a tractor/Beetle noise mind!!

I didn't have a 'handy assistant' available this evening to block a rag over the tailpipe whilst tackling
the front end up on ramps - fitted a new centre sphere and full track rod with new tracking/alignment!!

The early 2.0i cross box would cause issues fitting up to the TCT cat/centre connecting stretch even
if the rear box would mate if you compare it with the 16v (same as 2.0 TCT):



There's some brilliant prices on base spec 2.0i boxes but the awkward job would be getting a front
connecting pipe that is cat compatible!? Guess I'd be hoping to fit virtually all the base 2.0i setup if
it's easier/cheaper to get and hope a TCT cat fits?


All the best,
Andrew

Go back to the MOT tester and ask them to show you where it's faulty, they could always be wrong.

oh begger, i detect a problem.........but first, the cat to exhaust flange is in the same place, is the same fitment and size as the N/a cat so no worries there, its just the cat to turbo pipe that is smaller than the N/A's

Now the problem, the system pictured above for the turbo and 16v (ignore the cats as they are all different) is the same as the one my 8v N/A had originaly, it was a pita so i swapped it for the tct estates system from the cat back, i had to cut the tailpipe shorter as the estate has a longer tailpipe than the hatch but anway.............the tct estate had the exhaust thats pictured above for the 8v N/A.............so my experience is that the pictures for 8v tct and 8v N/A above are crossed over...............never simple is it

D

Unfortunately I can't help with Andrew's problem but ref your smaller pipe on the TCT Dean, basic physics say that pressure, volume and temperature are related. As a fair amount of energy is being removed from the exhaust gases to drive the turbine, it's logical that pressure and/or volume will reduce; ergo a smaller pipe is needed.

Andrew,

I kept the full exhaust system from the Turbo Onyx I broke. It looked to be in good condition. How do you fancy a direct swop for a 2.0i non cat system that would be compatible with my G Plater?

I can take pics etc if you are interested. Don't forget that this car was never running, so I can't guarantee its integrity, although it looked fine.