CAT life

[Helsbyman]

How long should a catalitic converter last as mine is 13yr old and i have been told to replace it
If it does need replacing any suggestions as what to get one. I am thinking of a 200cell sports one but where to buy
Have looked on ebay but they are universal or ford etc
Thanks

[mgtfnut]

My 02 TF passed it's MoT last week, the emissions were spot on. Two years ago the mild steel downstream flange was excessively corroded, so I got a new flange welded on. Despite all the man-handling, it's still working fine.

I tried a Rimmers new one, but the lambda sensor socket was in the wrong place and had to be returned for a re-fund

I would suggest cats last as long as they work and are structurally sound - why bother.

[Bazzajay]

The Cat on my 2000 was replaced last year at 86,000 mls. But, I had to replace a Cat on a Citroen I had a few years ago, when the car had done only 56,000. So you can never really tell.

[floozy]

My 2001 F is still on its original cat (currently on 110k+ miles). Like Jerry's, the flange rotted a few years ago so I got a new one welded on.

[Charless]

I replaced a 20 year old OEM one last year for external rot only!
I believe a well tuned K series doesn't need a cat anyway - the emissions were designed to be lower but subsequent one-size-fits-all legislation forced the mixture to be enriched to make the compulsory catalyst work at all.

[Rob Bell]

My MGF still has its 21 year old catalytic converter and sailed through it's MoT in January. I suspect that it won't be the internals that will lead to its ultimate demise, but rather external corrosion as Charles describes... It's already discarded its external heat shield...

[Helsbyman]

The reason i asked was i took my car to a rolling road gathering last Saturday and it should have 175+ ps and it only showed 119PS and he said it could be the cat but I think I would have noticed 1/3 lack of power plus the car will pick up and go at 70mph in 5th, it's a 160 VVC .

[Rob Bell]

The question there is whether the catalyst has become restrictive. When last I rolling road tested mine, it had essentially the same power and torque as it had 10 years ago. So it is not an age thing.

Which isn't to say that it is not a restriction in your exhaust system. Catalysts can become restricted - presumably particulate matter for partially catalysed reactions. It may reflect the kind of use the car is put to. But the same can be said of carbon build up within the cylinder head.

If largely urban/short journey use, the engine can become sooted up. The best/ most fun solution for this is a track day. Or the "Italian tune up" (ragging the car to within an inch of its life!). I always find that my cars run smoother and more powerfully after a good track session. I haven't done a "before and after" rolling road session to proves that it works - so it might be placebo effect, but I do know from experience that engine de-coking products made no difference to my car on the rolling road when tested soon after a Donington track day!

Were there any other TF160s at the same RR day you attended?

[Helsbyman]

Hi Rob
No there were no other F/TFs, all the others were Bs and a 1955 TF, As for an Italian tune up I do one ever 10-20 days. A 20 ml run with an up hill run at 5000-6000 rpm in 4th. The hill is 1 in 10 and 1.1 miles

[apiebyanyothername]

My MGF still has its 21 year old catalytic converter and sailed through it's MoT in January. I suspect that it won't be the internals that will lead to its ultimate demise, but rather external corrosion as Charles describes... It's already discarded its external heat shield...

It tends to be more what you do with them that limits the life. Loose catalyst in the can will destroy one fast that you wouldn't believe it ( the ceramic honeycomb disappears out of the exhaust pipe!). Catalyst only works while there is precious metal exposed to the gas stream, which is why it has to be lead free and why carbon build up can cause problems increasing the light off temperature from the 450°C. If you're lucky a good hard thrash down to the south of France ( or Blackpool ) can burn off enough carbon ( or move enough lead) to make the catalyst reasonably well. Original equipment catalyst tend to last longer as they have a heavier precious metal loading than aftermarket catalyst i.e. a larger margin of safety ( in the early days OE catalyst had to be garuanteed for 100.000 miles or three years) - Its up to you to decide whether the additional cost is worthwhile. The precious metal loadings have steadily gone down over the years. The catalyst of both types are all made in the same factories. I've never yet had to replace a catalyst, I have however had to replace the O2 sensor and then had to give the catalyst a little time to recover. I agree with Rob Bell about the heat shields - we have three catalyst equiped cars in our household and they've all
left them laying in the road somewhere.