Hello,

Does anyone out there know where to find a vacuum line diagram for a XKR with a 4.2l supercharged engine. I’m trying to figure out where the vacuum lines are supposed to be attached for the fittings in the attached photos? One goes to the Fuel Injection Pressure Sensor, one is about halfway down the top right of the supercharger and the last, unknown part, was attached to the intercooler crossover hose with a clip. There may be more that I haven’t seen. I hardly touched the “unknown” (no part number or markings) part and it broke off the clip. There were no lines attached to any of these parts, so I have no idea where to start. A part number for the vacuum line “harness” would be great. I did find pieces of the original lines, but they appear to have broken up long ago.

Vehicle:
2009 XKR Supercharged 4.2l

Thanks,
Andy


Fuel Injection Pressure Sensor

Fuel Injection Pressure Sensor overhead

Fuel Injection Pressure Sensor vacuum connector

Fuel Injection Pressure Sensor overhead with vacuum connector

Supercharger vacuum port with connector and piece of hard line

Supercharger vacuum port


Unknown part that was connected via clip to the intercooler coolant hose crossover

 

@Caracal13 Welcome to the Forum! You'll find many knowledgeable and helpful members here. You'll need the Workshop Manual (4.2L Version) to properly diagnose and repair your 2009 XKR. You can download it here:
JagRepair.com

The Road of Life is short, so enjoy the ride. I hope you enjoy yours as much as I enjoy mine!

Stuart

 

Here's a pic of a repair I did to the plastic hose combo that breaks down - the watchamacallit hose in my pic I think is maybe the fuel sensor as you are calling it.

 

I found it. The part number is AJ811093.

 

Great find and thank you for reporting back with the part number and a picture!
We get so many dead threads with nothing ever answered or solved.

Did it fix your car?
.
.
.

 

Clubairth1,

No problem. I hope the vacuum line part number and photo helps.

I did get the car going. It turned out to be the main fuel injection connector for injectors 2, 4, 6 and 8 was not making good contact. I pulled it apart and reconnected it. It seems to be fine now.

Thanks,
Andy

 

McJag222,

Please see the updated photo below. What appears to be a valve (yellow oval around it) connects to the vacuum lines on one side (bottom in the photo). Does the other side (orange arrow) connect to anything?

Thanks,
Andy

 

Mine follows this layout to connect with secondary air injection . Dont think American spec have this, Part number for secondary hose C2P3419

 

No it doesn't connect to anything - not sure what the device does though.

 

ChiefyO and McJag222,

Have a look at the photos below. What I have been calling a “valve” actually is a valve. I disassembled mine and found that it is a one-way check valve. One side goes to the actual vacuum line and the other side is simply capped off. ChiefyO’s car has the same valve (inside 'yellow' oval on his original photo), but the other side is not capped off and is used by the additional vacuum assemblies that are outlined in 'red' in ChiefyO’s photo. It appears that instead of designing a different vacuum line assembly for cars without the additional vacuum assemblies, Jaguar simply capped it off. Smart, saves them money. So, that brings up a question. For cars without the additional vacuum assemblies, why not simply run a vacuum line directly from the supercharger vacuum port to the port on the Fuel Injection Pressure Sensor and delete the rest? The rest of it is nothing more than a potential failure point.

I presume that the supercharger vacuum 'system' works like this. As the RPM increases, the supercharger creates higher vacuum pressure thereby increasing the negative pressure on the Fuel Injection Pressure Sensor, which, in turn, causes the Fuel Injection Pressure Sensor to 'call' for higher fuel delivery and thereby creating more horsepower which means more fun. Thoughts?

Thanks,
Andy


This is the one-way vacuum check valve assembly minus the clip that holds it to the intercooler crossover hose. The clip is not part of the vacuum line. The clip is zip-tied to the vacuum line to keep the check valve from flopping around.


This photo shows the one-way vacuum check valve components. Left is the cap, center is the one-way check valve and right is the female connector for the actual vacuum line.


This is ChiefyO's photo showing the additional vacuum assemblies (outlined in red) that actually use the one-way check valve for vacuum. I added the 'yellow' oval outline to illustrate the one-way vacuum check valve.


This is the Fuel Injection Pressure Sensor. The yellow circle in the center photo is where the vacuum line is connected. Left photo shows the sensor with the Ford part number (3R3E-9F972-AA), center photo shows close-up of the vacuum port with partial line connection and right photo shows overhead view.


Why not run a vacuum line (yellow line) straight from the vacuum port on the supercharger head to the Fuel Injection Pressure Sensor and simply delete the one-way vacuum check valve (red 'X')? Of course, this is only for vehicles that do not have the additional vacuum assemblies like on ChiefyO's car.

 

ChiefyO's car is a 2007 and in the UK.

I dunno, hard to tell if that extra pipe going to the front of the car is actually connected to the supercharger vacuum circuit. Why they included the check valve - I'm stumped. Local mechanic said he would use that as a port for a smoke test.

These look totally different to later model pipes:

https://www.jaguarforums.com/forum/x...arning-193275/

 

Have a look inside the 'yellow' circle I added to the photo below. You can see where the female connector is connected to the check valve. Perhaps the check valve is to keep pressure from bleeding off the two additional assemblies. The assembly by the radiator looks like an air tank and the one by the thermostat housing looks like a solenoid.

 

the only other vacuum line is from the blower inlet elbow to the bypass valve.

 

Secondary Air Injection System issues - RESOLVED - Jaguar Forums - Jaguar Enthusiasts Forum

Good explanation of the Secondary Air Injection System