Any downsides to removing the secondary air injection setup?

4.2 V8 32v Naturally Aspirated - 414 bhp
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Dave_M
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Any downsides to removing the secondary air injection setup?

Post by Dave_M » Sun Nov 14, 2010 5:16 pm

As per my other thread, I've got an emissions warning light re secondary air injection malfunction. I don't yet know what's failed, but it could be expensive to fix.

From the MRC car update thread, I see they've completely removed the secondary air injection system and used the space freed up to provide a 3" cold air ram feed to the airbox, thus ditching the troublesome air box flap (and mine is currently stuck closed). Depending what needs fixing on mine, this could be a cheaper option than repairing the system, but are there any downsides?

My understanding is the system only functions for a minute or so on startup to heat the cats up quicker. So removing it shouldn't affect ability to pass emissions test at MoT. But will the cats life be shortened?

Cheers
Dave

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Ice_Coffee
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RE: Any downsides to removing the secondary air injection se

Post by Ice_Coffee » Sun Nov 14, 2010 11:23 pm

I am not claiming to have any specific knowledge on the matter, but I would not have thought it would have had an adverse impact on the cats as most cars go on fine without this system at all.

neckarsulm
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RE: Any downsides to removing the secondary air injection se

Post by neckarsulm » Sun Nov 14, 2010 11:35 pm

But will the cats life be shortened?
Only if you run it over
[youtube]https://youtu.be/-I1Ok9LTn6o[/youtube]

adsgreen
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RE: Any downsides to removing the secondary air injection se

Post by adsgreen » Mon Nov 15, 2010 12:01 pm

I can't see it being a problem - it's purely to do with the cold start emission regs where the emissions have to be below a certain point so many seconds after a cold engine start.
Don't even think this is tested in MOT either as you can't really get the engine cold enough.

dominic1
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Re: RE: Any downsides to removing the secondary air injectio

Post by dominic1 » Mon Nov 15, 2010 4:30 pm

quote "neckarsulm"


But will the cats life be shortened?



made me laugh

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