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Hi all, i would like your views both positive and negative on the practicality of carrying out problem solving and rectification on electrical problems and other problem issues with the xj8 and x308 models.I fully understand that it is down to each individuals practical knowledge and whether they would prefer to look after their car or have it done by experts.
The reason i am asking for views is in response to the forum article in the latest issue of the mag on the lack of available information data for the model and that none will be forthcoming.
As an enthusiast of all things Jaguar i am really concerned about owning my x308 in that if something(electrical) goes wrong i am forced to take it to a Dealer or Independent Garage because i am told "don't do anything to that" it will ruin your electronics and it will render your car useless unless you have the expensive software to diagnose the problem.
Before i bought my x308 i did think long and hard about it because of the electronics in the car,maybe i didn't think long enough on how practical it is to maintain myself.
The car i have is great to drive but as it gets older it will surely need to have some work done and i must admit it worries me that i will not be in a position to try and diagnose the problem without having to take it to a garage.
I look forward to any comments that anyone may have on this.
Best Regards Graham

Graham , valid concerns indeed

personally, i want to carry out as much maintenance as possible on my car myself , this does however mean lots and lots of research , usually online , to find out the best approach , and solutions

this info, as you mention is limited, BUT it is in the most part out there in one form or another, it just takes time to track down

i recently had an MOT fail due to over fueling, the car was throwing the code for a faulty O2 sensor ( upstream ) , but at £230 each, i wasnt going to just throw one in to see if it worked,

i actually bought some OBD2 software and a lead to plug into my laptop to pull the codes , the thing was, both sensors were showing faulty , so i bit the bullet and booked it into Jag for a full diagnostic, they confirmed the sensor ' fault ' but informed me it was actually the ECU not telling them to work , it was the ECU that was actually faulty as they confirmed the O2 sensors were good

i will point out that Jaguar were the only real option for this diagnostic , as no garage i phoned ( non Jaguar specialist ) wanted to know, not that i would let them loose on my car with their limited knowledge of my car

result, new ECU required @ £2500 , ouch, no way i could do that,

i ended getting a matching ECU on the net for £230 , it has to be identical, but even then it will still need programing into the car by Jag as it wont run....... , which they did for £100

what i'm trying to say is that you can do a lot of the work yourself, but you do have to take it to the dealer from time to time , i have just replaced the lower wishbones myself, bought my own press to do it , Jag wanted £800 for the same work, total cost to me was around £220 , but i get to keep £120 worth of press............a big saving

i must say that i am very friendly with my local Jag dealership ( H A Fox Cheltenham ) , as i get lots of parts for my XJS project from them through the JDHT, and i get to pick their brains about working on the XJ8 to , lol

in the end, its a cost thing, i know that one day i may have to spend even more money tring to fix something i made wors by having a go myself, but thats the financial risk i take for owning and running such a nice car , ( 1999 XJ8 4ltr Sovereign in seafrost )
http://www.talkphotography.co.uk/galler ... Small_.JPG

BB

Hi BB thanks for replying.
I do a lot of online research mostly via Jag Lovers and also on our own jec forums.
I do agree there is a price to pay for owning such a great car but it does seem that it eventually needs a trip to a Dealer to complete a lot of problems and i would rather try to look after my own car and i know then what has exactly been done.
I feel a bit fortunate at the moment that my Super V8 has only done 17k and it gives me some breathing space to finally decide what to do. Fortunately the Super V8 went through the MOT last week with no problems apparent.
I have bought a Double 6 which i can do most jobs on and i suppose you get an intimate feel for the car when doing the work yourself(my wife can't understand how i can get intimate with a car ).
Thanks for your views and happy motoring.Graham

Graham,

There is information out there! If you have not already got a copy then get the Jagaur Heritage CD ROM which contains all the wiring diagrams. Whilst it's true that you can't "see inside" some of the ECUs without a suitable reader to access the car's diagnostic port, many of the car's quirks can be solved without the need to do this by analysing what's going on outside the ECU using the wiring diagrams. Note that to access the diagnostic port you can get hardware bits and software to fit to an average laptop computer - you don't need to fork out 6 grand for a dedicated unit.

Brian,
thanks for the reply.
I have the JDHT CD which i admit i have only taken a cursory glance at but i will take another look at,thanks for the suggestion.
Also thanks for pointing me in the direction of the bits to fit my laptop to connect to the diagnostic socket,i will certainly look to do that.

Hi,

If you intend to perform diagnostics I would suggest that you purchase an OBDII tester with CANBUS capability and ideally one with the Jaguar extended fault code set.

I personally use an AutoXray OBDII tester and a Launch CReader data logger on X308s together with a good DMM. The AutoXray unit has the Jaguar codes but the unit that I have only displays the fault code so I have to then look up what the code actually means (not usually a problem). Note: These testers are only for performing engine diagnostics. To test other systems then a more expensive tester is required. I believe Gendan makes a suitable system (AutoEnginuity). Does anyone have any experience with this tester?

Regards,

David

Hi David,many thanks for the detailed info,i will investigate.
Graham

David,
I have now purchased a scanner Maxiscan MS509.It has interigated the car and has come up with a pending code P1637.This explains why the car has been idling poorly.I will post a question in the relevant bit of the forum.Thanks for your help in pointing me in the right direction every one.
Graham

Graham for the record.......what was the problem re the poor idling?...Joe

Joe,this is the reason for posting in the Electrical section to get a possible view from other members who may have experienced this i.e P1637.This code can be found in the JDHT CD with full explanation which seems to be triggered when engaging cruise control.Graham

Upon investigation re rough, idle i have found a broken T piece with the vacuum pipe from the throttle body routing back to the monitor relays.The vacuum pipe was just hanging loose and i have to tape this to the T piece until i can locate a new one.The idle seems to be spot on now having done the dtc.I suppose its just a coincidence that the throttle body has just been replaced by a dealer and i get this situation.
Graham

Graham take it back its part of the job and a possible cause of the problem.......sucking air causing lumpy tick over.......

Joe,thanks for the suggestion,but i will sort this myself and then i know the job has been done.Graham

Hi all,for interest to anyone that may get the same problem i have had on my Super V8, the part number for the replacement item is NCC3094AA.It is in fact a four way white plastic item as opposed to a "T Piece".Mine was broken on one of the outlets,and the vacuum hose was just hanging in the engine bay,which has a return back to the abs and tccm monitors.This was giving a rough idle and cruise control would disengage and issue a fault code.It took me 10mins at most replace including taking off the protective engine covers,the part cost under £1,yes under £1 so i pushed the boat out and bought 2. .I have tested the car today and dare i say it,the cruise control seems to work ok and the revs have returned to normal.These were a non stock item at the dealer but it took only 3 days to arrive when ordered.
Graham

Graham good result, not much cost,and sorted it yourself....top outcome...
Im going back into the olden days when the vacuum pipe would either perish or come off, leaving you with lumpy tick over and it also affected the advance and retard on the old type distributers.......it seems things haven't progressed as far forward as we thought.....happy motoring now eh?........Joe