Hi everyone. So ive been messing with my xj12 here and there, getting some work done on it and yesterday while i was looking under the hood i noticed this thing with a hole underneath and it looked like it was missing a cap or something to cover that hole. I reached behind the engine and found the piece that goes there but i feel like its still missing something can anyone help? Im sorry i cant name any of the parts i really dont know much about the jaguar.

This is the thing i noticed first that had that hole in it, i found the part thats supposed to cover it but i would like to know what it is and how its supposed to look

This is the second thing i found. Can anyone tell me what it is?

 

Hello Roger,

That is the cover for the windshield wiper motor and mechanism. There is a round hole at the bottom of it. I have never removed it so I don't know if there is a separate part that may have fallen out. The picture looks right to me.

The other part behind the engine I believe is the Air Switching Valve (along the big hose that splits and goes to each air rail - the large nut to the left in the foreground). It will have a small hose attached that goes to another small valve at the rear of the right intake bank. It's all part of the USA spec air injection emission controls. I would have some trouble explaining how it all works! But in general, air injection occurs at startup to make sure any and all fuel that remains in the exhaust fumes, is burned before it hits the catalytic converters. Since the engine fuels more at cold startup, the extra injection of air at the exhaust manifolds or valves makes sure any excess is burned off.

 

Wow! Thabk you very much, SleekJag12. Do you knkw if the valve is supposed to have anything attached to it? Or does it look right in the picture?

 

Can't really tell from your picture, but the valve is only a mechanical device and if it has two large hoses and one small one connected, it should be fine.

Of interest is that the air injection tubes connect to the intake sides of the engine, right next to each intake runner. So there must be ports where they connect that send the air to the exhaust port area inside the head. But I have not seen a V12 head off the engine to check this out this plumbing feature.


The small metal vertical tubes are visible here, B bank (left side). 1 and 6 tubes are angled to reach.

Go ahead with your other more important questions, Roger!