Question(s) about removing the emissions equipment from the XK 6 cylinder engine? I've got an '86 with all original emissions equipment on it, came from California. I'm in a no smog check state so I don't have to have it. However, I am not interested in creating dirty air just because I can so I'd like to understand better what is the emissions equipment is actually doing on our engines and what would removing it affect? What benefits would I be gaining by removing the equipment?

Thanks for any insights you can give me.

Eric

 

removing the cat will increase your nos outputs, california dmv is hard on that, if you can remove that cat, that will decrease the engine temperature which cause the tappet guides to slide up and down, calling for a stake down kit to be installed...I would also remove the resonators. always thought that removing both will let your jag breathe better and have slight more power...put a high flow filter in there and you'll have much more air going into the car..

 

Thanks, appreciate the feedback. Any idea what the smog pump is doing/affecting?

Thanks again,

Eric

 

On a cold engine it injects fresh air into the exhaust ports. After the engine is somewhat warm (157ºF or something like that) the air switching module triggers the diverter valve on the back of the air pump...which in turn directs the pump output into the air cleaner cannister.

The air injection system really doesn't have any seriously negative aspects...except perhaps the 2-3 horsepower (if that much) that it takes to turn the pump. Most commonly the system is removed because the pump is noisy (or seized) and/or to de-clutter the engine bay.

Since the system operates during such a small window of time the overall environmental impact, if it was removed, would be minimal.

Technically speaking it's illegal, on a *federal* basis, to remove emissions equipment. I don't think the FBI will be chasing you down, though :-). I live in a "no emissions testing" county myself. If that ever changes, hoo boy, LOTS of people around here will be in a real jam trying to return their cars to legal configuration !

But...I'm rambling.

Cheers
DD

 

I have an '86 XJS v12 I have removed the air pump. what other emission components can be removed related to the pump..
I also plan to remove existing air cleaner assemblies and install K&N style air cleaner, what do I do with the various rubber tubes that are attached, I know the air sensor needs to be used. what can i plug
I have also removed the a/c compressor as well as the fuel cooler (which wasn't working) My fuel temp sensor was broken off and super glued back, so that's not working also.

 

Eric,

I'm in NC... and decided to remove my air injection pump, all the associated plumbing, and the air rail some time ago...
I didn't notice any additional horsepower, nor did I see any negative aspects of doing it...

The one super positive thing about doing it was it cleans the engine bay up dramatically. Access to the left side of the engine bay is opened up so much, and getting to the plugs is way easier too..
It's all straight-forward to do... And I can help you with the correct plugs for the head if you decide to go that route...

David Boger

 

David,

Thank you. I may take you up on that. I agree the main thing would be to declutter the engine bay. I like looking at my engine, especially a straight 6, and the more engine and less hoses the better.

You coming down to the Eurofest car show? I'd love to see your engine. I'll be entering my '86 this year.

Take care,

Eric