Air pump air rail question

Well I finally got over to see my neighbour and look at his new purchase of an XJ-SC.
It turns out it’s a 1986 model. As I look in his engine bay I noticed he didn’t have the air pump air rail set up.
Was this a deletion on Canadian spec cars up to this year?
Which begs the question I know we’ve talked about before, is it required or does it get coked up on the air tubes? Is there a maintenance procedure to clean them or do you just yard out the system. If it gets plugged on the air tubes will it affect the operation of the car or will you smell exhaust fumes?
What would be the pros and cons of removing it ?
Here’s a picture of of his car.


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I would think it would be a US only emissions thing, but not sure. My 1988 US model had the air pump.
I removed mine, as we have no emissions checks here in Washington State anymore.

You can chuck it all, but the only 3 issues:

  1. The air pump pulley also drives the AC compressor. I removed mine, as I removed the AC too. My ultimate plan is to move the Alternator up to where the Air Pump was so I can put back AC. So much more room w/o air pump.

  2. The holes going through the intake manifold to the exhaust need to be plugged up. Or else you have 12 tiny exhaust leaks. Easy enough, lot of different ideas out there. I ended up using steel plugs with a tiny bit of JB-Weld. The Vee looks so much cleaner/nicer with air rail removed.

  3. The big metal pipe that goes along engine on A bank side, it’s impossible to remove unless exhaust manifold is out. So I just left mine.

the air pump was not required for all markets , I don’t know if /when it would have been mandatory for you car in Canada
But my 1993 coupe has it, because it’ a Japan market car, while European cars never had it
so the car can do without it, there’s a jokey pulley to keep the belt
swapping the pump for the pulley wouldn’t be legal if your car is in a state where it was mandatory at the time
and yet if it’ was there, the hoses would be cooked :grinning:

I was just reading the write up by Bernard Embden of his removal of the system. It must have been a North American US California emissions thing that migrated to Canadian spec cars.
I can just imagine some worker at the Jaguar factory drilling all those holes trying to line up the air tubes. I wonder at the end of the day if it actually improved emissions numbers.
I see Bernard used a rubber stopper off a chair leg to plug the big steel pipe hole.

If I remember, it only injects air when the engine is cold, to get a cleaner exhaust. Secondary Air Injection.

My 97 Volvo had something similar. Only ran for like the first few minutes when cold. I think same with the XJS V12.

It adds O2 to any unburned fuel in the exhaust manifold, I think actually combusting, making for a cleaner exhaust. All of this just to make the first few minutes not so polluting.

Must shut off before the EFI goes into closed loop, because the injected air would convince the oxygen sensors that the engine is running lean.

Those of us that have the 6.0L are painfully aware of the FF67 code.
The Lucas 36CU is designed to periodically turn air injection ON when engine is running at normal conditions to check the response of the O2-sensors,

Sounds great in theory, but in reality, the ports of the air-rail get plugged with deposits and when the air pump is energized by the ECU, very little oxygen enters the exhaust.
As a result, the O2 sensor does not see the lean condition expected and the Check Engine light comes on.

I live in a State where my car is a subject to biannual inspections. The only way I could make sure I pass every time (CEL illuminated is an automated NO) was to have Roger Bywater disable the random test.

I don’t have the tests in the stste where I live. But I did as Sbobev and had Bywater send me an enhanced chip for my 36CU. And had him disable that FF67.