de-catting c5?

sonoramicommando · Post by **sonoramicommando** » 11 Oct 2011, 10:04

Can I de-cat c5 without causing some sort of ECU to freak out?
By that I mean, either cut and replace with a test pipe (i suppose x2 test pipes for each bank) or smash out the innard.
Cheers,
Sam

Post by **Paul-R** » 11 Oct 2011, 10:20

If it were a diesel then yes but I think you might have problems with the Lambda probe signals in a three way cat on a petrol engine.

sonoramicommando · Post by **sonoramicommando** » 11 Oct 2011, 10:33

Drag - it's a v6 petrol.
I haven't checked the price but it's bound to be pricey (times 2).
I suppose there are two oxygen sensors, one upstream and one down stream?

addo · Post by **addo** » 11 Oct 2011, 10:57

Three, possibly - if it has light-off cats for each bank.

den169 · Post by **den169** » 11 Oct 2011, 18:46

I think starting sometime next year any car that should have a cat and hasn't will fail the mot.At least thats what my mot tester son in law to be told me.

sonoramicommando · Post by **sonoramicommando** » 11 Oct 2011, 20:21

What's a "light-off cat"?

On Citroen Service for my VIN, it shows there are two oxygen sensors per bank - which must mean that ECU will compare the some numbers pre & post cat. And it's bound to kick up a fuss if both numbers are the same with a gutted cat.

den169 - Do you mean no cat = MOT fail or no "functioning" cat = fail? If its the former, gutting the cat (provided it doesn't cause ECU problems) is the way to go.

addo · Post by **addo** » 11 Oct 2011, 20:57

By light-off cat, I mean the smallish converters that are on some cars, immediately after the bank's collector manifold: