Hi there,


I have a 2002 XK8 which the motor was overhauled completely less that 3K miles ago. Timing, heads, gaskets, cooling system etc. All redone.


I have 2 issues remaining to resolve.


1. Intermittent restricted performance message appears. Code indicates knock sensor issue on bank 1.


2. Coolant level light stays on continuously - already changed the sensor light stay on.


On the knock sensor, my question is where are the knock sensors located on a 2002 XK8 and does anyone have a procedure to change them out? Not sure if they are on top of the heads underneath the covers or under the intake.


On the coolant level message? Should I flush the tank and replace the cap again? Does anyone have a wiring diagram to see if I might have a broken wire someplace?


Thanks in advance!


Hany - Austin, Tx


Hany

 

check the wiring to the coolant sensor, may be messed up???

I know on my 03 the knock sensor is UNDER the intake plenum about inline with the 2nd injector, under the plenum. On mine I don't think you can get to it without pulling the plenum off!?!?!?

 

The knock sensors on the '02 can be changed without removing the intake manifold. I did not have any problem with lost nuts or fishing the lead up to the thermostat tower for connection.

The magnetic float inside the tank may be stuck on the tube it ride on. Use a tool that is not going to break anything to fish the float up off the bottom and ensure that it still floats and moves without binding. Something like a plastic spoon.

 

If the knock sensor cannot be lifted high enough to clear the mount stud, then remove the stud with an 'E' Torx socket and pull the stud out between the intake 'runners'.

You can re-install the stud and nut in reverse order.

bob gauff

 

my knock sensors connections are mounted on either side of the thermostat tower... you can trace the wires to the sensor which on mine are next to the valve covers at the top about mid engine. sometimes if the hose from the coolant fill tank to the thermostat tower has a small leak the resulting steam can trigger a short in the connection mounted there from the steam as it evaporates .

 

thanks Guys! I'll check the coolant float as advised. that should be easy.



The knock sensor, looks like there are multiple styles. Not sure what they look like on the 02 XK8 but will check on per all the replies. did anyone have a wiring diagram or know where I can find on in case I have to check the wiring?

 

The coolant light staying on is due to the magnet falling out of the float in the expansion tank. It is almost impossible to reinsert it. You will need to replace the tank or short the sensor out and forget it.

 

Thanks EZ driver. I'm checking to see if I can find a new coolant tank locally. Curious, how do you short the sensor?

 

try motorcars ltd theyre located in tx.

 

Remove the connector, carefully, from the sensor and use a piece of wire or paper clip to short the wire side of the connector.