I am very close to getting my 1997 XJ6 back on the road after a few months of making various other fixes to the car that were ignored or poorly done by previous owners. However after taking a drive in the car yesterday I find that there is a pretty serious exhaust leak from the part of the system that contains the two center cats. I have looked at various solutions on line and a new part seems to be really expensive. I only paid $900 for this car and now that I have finished up a ton of small fix jobs to the car to get it back on the road I am dismayed that I might have to plunk down a whole bunch of cash to replace this one part of the exhaust.

Has anyone done anything cheaper to replace the Y pipe with the center cats? Would totally eliminating the center cats throw the engine management system off to the point where it would trigger a check engine light?

Any and all suggestions or general discussion about this would be most welcome.

 

Only the forward cats are monitored. The management system has no idea that the center cats even exist......so eliminating them should not trigger any problem as far as that goes.

As for 'general discussion' of the idea, eliminating the cat converters does have some legal and social implications but I'm not sure you wanted to go there so I'll leave well enough alone.


Cheers
DD

 

Check out the following thread as it discusses this very topic:

https://www.jaguarforums.com/forum/x...ntages-152568/


...still waiting for someone one day to have the need and desire to try moving the downstream O2 sensors behind/beyond the underfloor catalytic converter to see if the ECU thinks everything is still normal with the downstream O2 sensor moved. See thread above, discussing using the relatively inexpensive OEM non-cat Y pipe.

For those that want to save some money and future expense once their upper catalytic converters wear out, this would be a good option to keep everything running stock and not illuminating the CEL(check engine light).

Also discussed in the thread is another option to fit one of the oxygen sensor cheater/simulators (much more a cheater than any "simulation" going on with the "extender" type) that lets you mount the O2 sensor slightly out of the direct exhaust stream that supposedly fools the sensor into thinking it is sampling exhaust post-catalyst. These seem cheap, but who knows if they really work.

Like this:




But OTOH there is some intriguing information out there, say on YouTube that talks about building an electronic unit to simulate the O2 sensor which might be a much simpler approach. I have no idea if these really work, or would work in our system. But interesting.

Like this one:





.

 

Thanks Al

 

FYI, The non-catalyst intermediate pipe NNA6757BA is no longer available from Jaguar Classic parts. The non-catalyst downpipe CBC6373 is still available.

 

when I had the exhaust redone the shop made an intermediate pipe for me out of stainless steel, not a big deal, it's the downpipe that you don't want to have to spend money having custom made

 

Do you remember what sizes were used on the inlet and outlets of the aftermarket Y-pipe?

 

ill do it .

 

I don't remember the size, although 2.5 inch maybe, it was a standard piece of pipe that the shop had, but they also do custom exhaust.