p0327 knock sensor

[rob1xlb412]

hi all, i have just taken my xj8 out from under her cover, she has been covered for last 6 weeks, recharged the battery and restricted performance came up. my question is do i have to replace the knock sensor code p0327, or drive it for a bit and see??

[ptjs1]

rob1xlb412,

I assume that P0327 is the only fault code which is being held in store?

I would just reset the code, drive the car and see what happens.

Cheers

Paul

[Andy P]

Hi rob1xlb412,welcome to the JEC forums.
When my knock sensor failed the code would come back upon starting the car after clearing the code.
There are two types of knock sensor used on the XJ8 so be careful if you have to order a replacement.
Let us know how you get on please.
It would also be helpful if you put the year and model of your car in the signature of your profile.
It helps other forum members to give the correct advice.
I think this link should take you there:
ucp.php?i=ucp_profile&mode=profile_info
Good luck.
Andy.

[rob1xlb412]

Yes, sorry, my xj8 is a 2000 3.2 v8..x308..tried to clear the code but came back..i have got two replacements coming and will fit at the weekend, will let you know how i get on..

here is a pic..i will try and update profie as advised

[Andy P]

Hi rob1xlb412,
Thanks for posting a photo.
Your car looks very good,nice colour,same year as mine.
Good luck with the fitting of your new knock sensors.
Here's a bit more info.
The Knock Sensors are easy to replace,they are on top of the engine,secured by one nut:

Knock Sensor Position

You can check a few things before proceeding with replacing them.Is water sitting in the valley beneath the intake manifold. If so it will short out the knock sensor. If you have water it could be a valley hose is leaking. Also, look for water staining around the sensor.
You can check them for broken or damaged wires. If none of that is present then the sensor has probably failed.
Before putting the new ones in use some WD40 and a paint brush to clean the mating surface on the engine for good contact.
Take care not drop the new Knock Sensors,they are very fragile.
Tighten the nut to finger tight and then torque to 20Nm or 14 lb/ft.
If you want a workshop manual let me know and I will send you one using WeTransfer.
Take care.
Andy

[rob1xlb412]

Many thanks, thank goodness for google and you tube..i will let you know how i get on

[rob1xlb412]

thought id give you a update, upon further inspection, it appears that there is a small leak in the thermostatic housing and i think this may be responsible for the knock sensors fault, as the knock sensors look pretty new. So new plan of attack is, fit a upgraded metal thermostatic tower, replace some hoses as age etc, then see where we are. will keep you up to date

[Andy P]

Hi Rob,
Good idea to change the thermostat housing for the upgraded one.
That leak is the most likley cause for the knock sensor to fail.
Good luck with the work.
Andy

[rob1xlb412]

Cheers Andy, the rear two bolts on the thermostat housing are a real pain, have got a 8 mm crows foot coming, that should do it..one that you slide on, not one you fit on top, as there is no room..will be a ten minute job then.

[Andy P]

Hi Rob,
When I did mine I loosened the intake manifold bolts so it would lift up a little to enable me to get the rear two housing bolts out.
I replaced the original bolts with allen head bolts for the housing.
If you want to test your knock sensors they should read in the region of 200 ohms,if it reads considerably lower then it has failed.
Good Luck and take care.
Andy

[rob1xlb412]

Done it!!...sorted, tested the faulty sensor, it was reading 140 ohms, changed it and now all ok, the rear bolts were really fiddly but the crows foot was the way ahead for me...

[Andy P]

Well done Rob,
Glad you got it sorted without too much hassle.
Take care.
Andy