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My 1997 XK8 recently had its timing chains and chain tensioners changed. The car was returned with an intermittent fault whereby the wipers keep running when the ingition is switched on dipite the fact that the wiper switch is in the off position.

This doesn't always happen but if it decides to occur it happens most of the time. The wipers don't run continuously but give a couple of wipes at a time as if they are getting something from the intermittent wipe circuit.

Coupled with this I also have radio interference which wasn't there before the car was serviced. This is ignition firing related.

Has anyone any ideas about this?

Regards

Roger Wells

Just want to say: Welcome to the Forum and the Bulletin Board, Roger.
Sorry I can't halp you with your particular problem. I have owned my MY00 XK8 for over 2 years now and covered about 23Kmiles in that time, but have never heard of a problem like yours.
I hope some of our members on the forum will be able to help.
Personally, I would take the car back to the dealer/garage who did your tensioner/chains replacement, as it seems to tie in with when your problem started.
If you can't get any joy there, try to contact David Marks in Nottingham who is our very experienced Technical Advisor to the JEC Club and to this forum. You find contact details in the JEC magazine.
Hope you get it sorted soon so you can continue to enjoy your 8.

Karl,

Thanks for your thoughts on this matter. The garage who did the chains doesn't want to know. They are one of the independent Jag garages.

I have found that the earth connection on the bonnet was loose. This is on the left hand hinge at the front of the car. When the bonnet is reinstalled it is obvously easiest to tighten the top two hinge bolts on either side first (this is looking at them with the bonnet open) leaving the bottom ones loose. One of these has the earth connection on it. Both bottom bolts were loose so the garage must have forgotten to tighten them.

This earth connection seems to be associated with the wiper circuit from a wiring diagram I have. However this seem a funny place to connect the earth of a relay circuit as it relies on the hinge joint to to make the earth. I can understand that this is OK for the bonnet earthing but is not good practice for relay circuits.

Anyway tightening this earth connection has solved the problem while I have been driving the car but my wife reports it has done it while she has been driving. Could it be something to do with the steering column harness. the steering wheel gets out of the way when you remove the ignition key?

The car is now booked in with the main dealers who say they should have dionostics to deal with this.

One last thing I thought I might try is to disconnect the battery and reconnect again to reset the computers.

Roger,
I am glad you found the trouble - poor earth it seems does come up quite often as the cause of trouble. The same goes for a weak battery. The electrical system on these cars is extrememly sensitive to even a small votage drop. This is, of course, more prevalent for cars who are often 'resting' in a garage, etc. and don't have the benefit of regular longer runs.
It seems, indeed, a strange place to earth a circuit, I'll have a look at my car to see if it is the same. Does it look like original wiring or is it possible that is was done later in its life?
It is normal for the steering wheel to get out of the way when you remove the ignition key - these are very gentlemanly cars and make sure, recently retired folk like myself can get in and out a bit easier

Remember, if you disconnect the battery you will also have to reprogram the door windows so they know there reference position for partially dropping the window when you open the door.

Hopefully, your main dealer should be able to give you a reasonably general report.
Good luck and please report back after its visit to the dealer. Thanks. Roger - and out (excuse the joke, I am sure you heard it before

Roger. Would you care to enlighten us as to the independent garage that apparently started this chain reaction? Sounds like they need avoiding..

On a similar vein - my 99 XK8 wipers seem to park rather high off the lower part of the screen - yet the 'sweep' appears normal. I've only noticed it recently - could be that they have always done this but they stick up above the line of sight - bonnet to eye (if you get my meaning).
If I raise the seat more, my (rapidly diminishing) hair touches the roof...
Anyone else similarly afflicted? Wipers, that is - not hair....
Michael

Roger. Would you care to enlighten us as to the independent garage that apparently started this chain reaction? Sounds like they need avoiding..

On a similar vein - my 99 XK8 wipers seem to park rather high off the lower part of the screen - yet the 'sweep' appears normal. I've only noticed it recently - could be that they have always done this but they stick up above the line of sight - bonnet to eye (if you get my meaning).
If I raise the seat more, my (rapidly diminishing) hair touches the roof...
Anyone else similarly afflicted? Wipers, that is - not hair....
Michael
Similar in my case, I think, Roger.
I am 6'1" and find the seat hight adjustment excellent in the XK8. I usually have my seat set just above the lowest setting, which gives me still good headroom without bouncing my head against the roof when going over bumps. But, I also find, that sometimes I would like to see a bit more of the bonnet power bulge but the wipers seem to be in the way.

There is something that does annoy me about the wipers, when they are in use. Its the dull 'thumping noise' the right side wiper makes when changing from the upward sweep to the downward sweep. It does not seem to hit the screen surround but sounds more like the rubber blade.
I have tried glass polish but does not have made a difference.
Going down a boring motorway in the rain, that monotonous sound is mesmerizing and annoying. I wonder if anyone else has experienced a similar problem.
BTW, I have replaced the wipers with new Bosch ones to see if it helps but no.

Hi Karl ,
Just come across your post today , It sounds like a fairly common problem with XK's and is the aerodynamics of the drivers blade (which should have a spoiler on it ) altering depending on its angle of attack with the air flow over the screen (usually noisy at motorway speeds ) hope this helps ,

NIK 98 XK8 Coupe Antigua Blue N1XKO


P.S it's annoying isnt it !!!

Although I still have the slightly 'high' park on my wipers (see above), I get less thump with mine when operating since removing the aeroblade. As I seldom drive at 'points attracting' speed (officer), the wiper seems to stay on the screen. Mind you, I never willingly take the car out in the rain!
My bonnet/hood has the 'earth' cable on the hinge plate too - I assumed it was a bonding cable to reduce static on the radio/electrics. (Aircraft are smothered in them..).

Michael

I've posted a fix I did to the parking problem in the thread under General
John