Catalytic Converters

[Dykle]

I have a 2005 E 280 Sport with a V6 3 Ltr diesel in it. If I was to remove the Cats would it put the engine management light on? Many thanks

 

[LostKiwi]

I have a 2005 E 280 Sport with a V6 3 Ltr diesel in it. If I was to remove the Cats would it put the engine management light on? Many thanks

It's illegal and an immediate MOT fail if you're in the UK.
Why would you want to?

 

[Craiglxviii]

More powahhhhh..?

 

[LostKiwi]

More powahhhhh..?

Marginal with modern cats on most cars.

 

[Craiglxviii]

Marginal with modern cats on most cars.

Yeah but with K&Ns, come on...

 

[LostKiwi]

Yeah but with K&Ns, come on...

Troublemaker!

 

[Craiglxviii]

Troublemaker!

OP still hasn’t bitten though.
Why do people buy the lowest powered variant of a car with real performance promise, then suggest doing things like this to it..?

 

[Dykle]

It's illegal and an immediate MOT fail if you're in the UK.
Why would you want to?

Yes I am aware of the legal & MOT position but this was not my question. I had a regen issue with a 2Ltr BMW diesel & knocked out the CAT leaving the empty box. The car now ticks over better has more power and better fuel consumption and has no MOT issues.

 

[Dykle]

Yeah but with K&Ns, come on...

I take it you mean K&N air filters?

 

[LostKiwi]

Yes I am aware of the legal & MOT position but this was not my question. I had a regen issue with a 2Ltr BMW diesel & knocked out the CAT leaving the empty box. The car now ticks over better has more power and better fuel consumption and has no MOT issues.

Whether it was your question or not you shouldn't do it due to the legalities.

Rather than bodge something to get around an issue fix it properly as designed, especially where emissions are concerned.
If you don't have MOT issues that says more about your tester than your vehicle. Try going to a tester that does the test properly and see how you get on....

 

[Dykle]

Whether it was your question or not you shouldn't do it due to the legalities.

Rather than bodge something to get around an issue fix it properly as designed, especially where emissions are concerned.
If you don't have MOT issues that says more about your tester than your vehicle. Try going to a tester that does the test properly and see how you get on....

I only joined this forum yesterday in the hope of sharing knowledge with like minded car enthusiasts not to be lectured to! A little knowledge can be a dangerous thing!!!

 

[Dykle]

OP still hasn’t bitten though.
Why do people buy the lowest powered variant of a car with real performance promise, then suggest doing things like this to it..?

I am old school, I want to produce power by burning fuel and have no interest in hybrid or electric. I don’t have the funds to have a choice in what model which chosen power so my first Merc just needed to be a diesel and then I can work on it to resolve its faults like leaking oil cooler and coolant issues. I want my engine to be able to breath in and out freely and what ever power that produces is fine by me.

 

[V6Matty]

Leave things as they are regarding exhaust just a stage one remap will give you better performance and won’t make any difference to the emissions, removing the cats on the diesel does little for the exhaust flow unless your looking at stage 2/3 tuning, a simple stage one will take you to around 280bhp and 600+ tourques

 

[Dykle]

Leave things as they are regarding exhaust just a stage one remap will give you better performance and won’t make any difference to the emissions, removing the cats on the diesel does little for the exhaust flow unless your looking at stage 2/3 tuning, a simple stage one will take you to around 280bhp and 600+ tourques

At last a sensible reply, thank you very much V6Matty for your informative knowledgeable response.

 

[daibevan]

You will find that the cost of the expert answers you get on here (the quickest and the best) is merciless teasing and strong opinions.

 

[Craiglxviii]

I only joined this forum yesterday in the hope of sharing knowledge with like minded car enthusiasts not to be lectured to! A little knowledge can be a dangerous thing!!!

Sure. But don’t expect not to be given opinion either. What you’ve proposed is illegal. So, therefore, don’t do it.

 

[Craiglxviii]

I am old school, I want to produce power by burning fuel and have no interest in hybrid or electric. I don’t have the funds to have a choice in what model which chosen power so my first Merc just needed to be a diesel and then I can work on it to resolve its faults like leaking oil cooler and coolant issues. I want my engine to be able to breath in and out freely and what ever power that produces is fine by me.

Then that speaks poorly towards your morals and ethics. I’m alright Jack, but screw the rest of you!

I’m old school. So is LostKiwi. We both run big V8s, which didn’t cost us a fortune to buy (mine was the cheapest car purchase I’ve ever made in fact) and all of which fully comply with relevant environmental legislation.

Do you want your engine to produce more power/ torque (99% of peoples desires) or to breathe freely and accept the consequences (maybe increased power, definitely significantly reduced environmental performance)? I’d suggest the former.

Therefore there are options for you to take that don’t involve cat/ DPF/ EGR deletion which are fully legal and don’t contribute to the poisoning of children’s’ respiratory and nervous systems. Because, you must understand that that is where your initial idea will lead.

 

[Craiglxviii]

I take it you mean K&N air filters?

Yes. Otherwise known as Snake Oil (tm). Don’t use them, they offer zero improvement to performance. Standard paper filters work just as well and cost 1/5th of the K&Ns typically.

 

[LostKiwi]

I only joined this forum yesterday in the hope of sharing knowledge with like minded car enthusiasts not to be lectured to! A little knowledge can be a dangerous thing!!!

Indeed it can.
Removing cats will as I stated give very little improvement. Since it also makes a car illegal it's not worth doing.
As a car owner we all have a responsibility to follow rules, especially if you run a diesel given the highly polluting nature of diesel exhausts. NOx and particulates are known to be extremely harmful to human health and the environment.
Petrol isn't great regarding CO2 emissions but CO2 is a long term issue unlike NOx and PM which have immediate health impacts.
It's not for no reason that diesel cars are being excluded from city centres whereas older petrol cars are still ok.
If you choose to run a diesel and get the economy they provide you have a moral obligation to society to ensure it complies with emissions regulations, just as I have an obligation not to decat my V8s. Last year I replaced both cats on one of my vehicles. I could probably have avoided the cost by finding a lax MOT tester but didn't because it's my responsibility to ensure my vehicles are as clean as possible.
All emissions controls on all of my vehicles work as they should.

 

[matthew k]

Agree with the above, raw diesel exhaust stinks and is V unsociable. The power gains would be marginal, if at all.