What is this loose sensor/connector? It is near the back of the right (passenger) cylinder head. It has been like this for some time and no obvious place it plugs into. Is it perhaps some sort of ambient air temp sensor that is just supposed to be clipped up out of the way? Sure looks like it should plug into something.

I found this chasing a bank 1 and 2 lean condition codes I've checked the air intake bellows tube (was replaced a few years ago and still looks new), changed the fuel filter and MAF, confirmed 55psi fuel pressure, and still getting them occasionally. Car runs better with new MAF (power level noticeably better) but is now idling a little rough...feels like a vacuum leak. but not many vacuum hoses on the 2006 4.2L. Only other thing I can think is something in the PCV or evap system (read about the solenoid under left front fender liner, but no smell of gas when car is in garage).


Where does this connector with green tip go?

Connector on the right above right rear of cylinder head not plugged into anything

Thanks!
Doug

 

Does it go anywhere? There are multiple unused ones around the car.

Hunt around the electrical diagrams and you may well find it. Quite a "fun" thing to do instead of watching paint dry?

 

This plug is fitted with the green blanking protection piece, this shows that it is not used (the option is not fitted) to your car.
As said there could be several around in various places.

 

I chased my wife's Jag's lean codes quite a while. And yes - I smoked it to no avail. On a hunch I replaced the plastic bellows intake tube and throttle body elbow with an aluminum tube with silicone ends. Problem instantly solved.
My guess is that once the engine compartment warmed up, a leak would develop at the throttle body plastic elbow connection. What threw me off was that the lean code only showed up on bank one, which made me think it was an intake manifold gasket or and injector o-ring.
I guess it is just the nature of the beast to be "unique", even in failures. Ah well, smoke machines make pretty good power hitters.

The pictures are from their site:
https://www.minagallery.com/jaguar-x...take-tube-pkg/

Her Jag is not supercharged, and the pipe was a very good fit, and we retained the original MAF and air filter system.

 

I installed that Mina Gallery aluminum air duct kit in April 2019 after the May 2005 factory black plastic air duct and a September 2012 OEM replacement black plastic air duct both cracked and split at the accordion section after a few years of engine bay heat. Problem solved. That kit is well worth the money....

 

The Mina Gallery kit only appears to fit the early 4.0L cars judging by their pictures. The 4.2L cars have the breather connection in the 90 degree part just before the throttle body instead of up near the MAF. Do they have a different one for that?

 

The Mina Gallery kit indeed fits the 4.2 engines. When you place your order, just tell Chris at Mina that you have the 4.2. He will include the appropriate parts....

 

Thanks, he replied the same to my email this morning. I'm going to get this but in the meantime, are there any other vacuum connections I should check? Car still getting both bank 1 and 2 lean codes feels/behaves like a slight vacuum leak. I've spayed carb cleaner around all the parts that look relevant but no change. Am I missing any? Maybe the evap purge since read someone else had an issue with that solenoid?

- intake manifold gaskets
- intake manifold front metal plate (behind thermostat, since I did replace thermostat housing ~1 year ago when it leaked)
- left breather hose, length + both ends
- right breather hose, length + both ends
- all around throttle body, especially lower where 2 lines come in
- plastic intake tube bellows and ends (plus removed for visual inspection out in sunlight)

 

Just make sure you do not fit a cone air filter within the engine compartment as shown in the PJMoore picture, hot air is not your friend.
To get/maintain maximum power you need to draw the coolest air possible or your horsepower will suffer as the engine warms up. Keep to the factory filter box/air source.

 

I did not install the cone filter. The picture is from the vendor website. I wanted to retain the original air filtration system. I don't even use "high flow" air filters.

 

I have found leaks all over my engine. You gotta check em all and fix them. Cross my fingers I got it this time...

 

Absolutely.
Warm air is less dense, cool air more dense.
Cool dense air makes the engine more efficient and produces more power.

 

Oh for sure, Jag got that right with the airbox and snorkel drawing colder air from outside the engine bay. I run a K&N filter in there already, as I do in all my cars (and am careful not to over-oil them).

 

Hey AARcuda (great car and screen name, BTW): Any tips on other places you found air leaks that I didn't list above and should check?

 

Dougboost, be sure to spray some throttle body cleaner around the EGR valve behind and under the throttle body. I found a leak on mine there in the past. Also, the throttle body gasket is just a thin metal part, easily overtorqued and damaged. Spray around that area too while watching your trims. If they drop immediately, you've located it.

 

Jon - I have the Mina air intake on order and in the meantime realized while getting Halloween decorations out that I could indeed do a smoke test. We have a fog machine and it worked great, pointing out this tear in the underside of the stock air intake boot (I had to open it with my fingers for this pic. The way these rubber parts are molded to the plastic tube is definitely a failure point.

 

Glad you found your issue. The OEM black plastic air intake ducts are one of the lousiest parts on these cars. Enjoy your new Mina aluminum air intake duct knowing that you should never have to replace it....