Being overtaken by Reliant Robins!
 

Hi everyone from sunny Newmarket U.K. Well it's snowing actually!

Hope that somebody out there can help me with my current problem as it is very frustrating not being able to enjoy the full performance of this car.

The problem started about a month ago after I hadn't used the car for a while. I took it for a short spin and when I returned and restarted the car the amber light and Restricted Performance warning came up on the dash.

I checked the battery voltage and found it was under 11v with the ignition on. As the battery was old I thought it best to replace it with a 100 AH 950 amp CS new battery as I understand low voltage can cause problems with the computer and sensors. However this made no difference to the RP warning.

I put the car on an Autologic code reader and got the following fault codes:- P0202, P0203, P0205, P0208, P0327, and P1647. The first 4 codes are fuel injector circuit malfunction on cyls 2,3,5,and 8. The next 2 are KS sense circuit out of range ( low voltage) Bank A and heated oxygen sensor bank 2 circuit malfunction.

The codes were all cleared all the codes down and the car ran fine for about 2 miles before the RP warning came on again and the same fault codes reappeared. The engine itself runs really smoothly with no sign of misfire until you put your foot down and the RP kicks in.

I can't believe that 4 injectors on different banks would all go faulty at the same time and wonder if it could be a connector or wiring fault? Does anyone out there know where the injector wiring terminates or had a similar problem and knows of a cure?

Thanks for taking the time to read this thread and I hope that someone might have an answer to this problem.

First check your charging system, sounds like alternator problem.

Thanks Anders
 

Hi Anders, What makes you think it might be alternator? I don't know much about the scope of the code readers but I would have thought that it would have shown if there were any problems with the charging circuit. I know that the electronics are quite sensitive to voltage variations, so I will put a meter across the battery whilst the engine is running. The voltage gauge on the dash usually sits around 13v, but I know these are not always that accurate.

IT is possible that low battery voltage from a dysfunctional alternator can throw spurious codes but these are not usually among them.
It does sound like a wiring harness problem.
Start by downloading JTIS from the HOW-TOs - it contains everything you will need to address the problem logically.

Hi from cold Bury St Edmunds. I don't have the answer to your problem, but we do have an independent Jaguar specialist locally who may be able to assist. My XK8 is currently with him having a new rear subframe fitted (failed MOT due to corrosion). I can provide you with details if you require. Alternatively, a short trip to Norfolk to see Tony (XK Racer) may be worthwhile.

Hi Renaultvation
 

Thanks for your post. I often visit Bury and did't know there was another XK8 owner so nearby. Sorry to hear of your rear subframe corrosion, sounds like quite an expensive repair. I have been searching for connector blocks on the injector circuit but have found nothing so it might be useful to contact your jag specialist if you can give me the details.Hope your car is back on the road soon. Regards

Hi Rollo

I tried to pm you, but you may not be enabled yet. The specialist I use is Tim Revett who is based near the Sugar Beet Factory. His details can be found here: Tim Revett Prestige Vehicle Servicing - Car Servicing - Bury St Edmunds, IP32 7HX

There is another XK8 in Bury, but unfortunately it has a big wing attached at the rear!

Regards
Chris

Tamper Proof Screws
 

Trying to get to the ECU to check the connector and see if I can check the wiring for continuity. What could be simpler you'd think?
Just take the lid off the ECU container but no Jaguar have used clutch type tamper proof screws to hold the lid down. Have got two of these out but will have to persevere with the other two.
Who knows one day I may be able to drive the car flat out again but for now I'd be happy to just get the lid off to access the ECU. Do the ECU's go wrong often and can they be repaired or do you just replace them?

I had the same type of problems when I put in a new battery. Found out the new battery was half charged, so I put it on the charger overnight and problem was solved.

Thanks randyb. It is a new battery and I have never charged it, and the car has only been taken on short trips so I doubt if the alternator has put much charge in.
I will give it a charge tomorrow it must be worth a try, the old battery was definitely down on voltage which seems to be what triggered the Restricted performance in the first place.

Still trying
 

Have fully charged the battery but still on restricted performance. Got the cover off the ECU and cleaned all the ECU connectors but still no difference.

Has anyone else got any idea what else I can try?

Is it likely to be the ECU itself? it is an LNF141 OBC.

Any suggestions gratefully received.

Do a hard reset
https://www.jaguarforums.com/forum/x...connect-74146/
If the RP comes back can you read STFTs and LTFTs?

Bon soir
 

Thanks Steveinfrance, I will try a hard reset. Unfortunately I don't have equipment to monitor fuel trims. The fault codes were cleared with a Autologic reader. This cleared the restrictive performance for about 2 miles but then the faults P0202, 0203 etc etc all reappeared and RP returned. The engine ticks over very smoothly and runs fine until the RP kicks in!

Over taken again
 

By the way Steveinfrance I was overtaken by a Terrot 125 last week but I can still out run a Liebherr just!

The Liebherr always wins - except against an MBT (Main Battle Tank).

Hard Reset
 

Tried the hard reset, but no change, Restricted Performance comes up as soon as you turn on ignition.

I have the ECU out of the car and in the front room with me and I am now attempting a "mind meld" with the unit itself! It works for Spock so I thought it might be worth a try. Failing that I am going to contact the new Pope and ask for divine intervention.

I would like to try and sort this out myself but as you can see I am running out of things to try. My next step perhaps is to take the car to a Jag specialist and see what they make of it all!

I keep on about this but if you've got an Android phone buy a Bluetooth OBD dongle off EBay
Android ELM327 V1.5 Bluetooth Super Mini OBD2 OBDII Auto Car Diagnostic Scanner | eBay
and run an app called Torque on the phone.
You will get lots of useful live data including STFTs and LTFTs
That will help with your diagnosis.
Don't get into the 'throwing parts at the problem' (by all means throw them at the wall, sometimes helps) until we've got into things a bit further.

OBD dongle
 

Hi Steve, thanks for your input once again. The Bluetooth reader seems a real bargain. I am not very good with modern technology, so am not sure if it will work with my phone? It's a Samsung Galaxy Ace with Bluetooth and I also have an iPad with Bluetooth but am not sure about the Android bit.
I also notice that it doesn't list Jaguar on the comparability list, but obviously it sounds as though you have tried this device and it works.
At the price it seems well worth sending for one, and hopefully you will be able to advise me how to use it to help diagnose my current problem as I not really conversant with the application of short and long term fuel trims!
Many "tanks"

That's the one I bought and it works fine with a Galaxy.
Worth the £3 for the professional version of Torque once you've got it working with the free app.
You plug the dongle into the car, turn on the ignition and the dongle lights up like a christmas tree.
You then pair it on your Samsung.
The only trick is, once paired, you have to get into the torque menu and select 'generic crappy bluetooth' (or similar) as the paired device and then connect.
PM me if you get stuck - it will stimulate me to do a 'HOW-TO' on Torque.
It's an amazing app - all sorts of useful live data including fuel pressure, 0-60 times etc etc.

OBD 2 Compliant?
 

Steve, Does my car have to be OBD 2 compliant to use this? Your vehicle is 2004 but mine is a 2000 model and I am not sure if it OBD 2?

And for the rest of the world who dont know what a Reliant Robin looks like ,,,,,,,Ta Daaaa!!

Del Boy eat your heart out!
 

Thanks for clarifying that Five Speed. Looking at the Reliant you can see how similar it is to the XK8, shame about the missing front wheel though!

I'm pretty sure I've seen it working cars a lot older than yours. For the price of the dongle it's worth the gamble.
I believe the OBDII standard dates from 1996-ish.
Found a video on how to connect.
The dongle password is 1234

Blue tooth and Wifi OBD2 Readers
 

Damn the expense, went mad and ordered the suggested blue tooth reader for the android phone and also a wifi reader to link up to my iPad. So between them hopefully I should get some sort of read out from the car!

I can't believe the price of these devices, who knows they might even work and I can monitor the engine whilst I drive.

Watch this space for the next instalment, one day soon perhaps my RP will be a thing of the past and I will once again experience the thrill of my head being pushed back into the headrest.

Did you know that the standard XK8 is faster to 100 MPH than the XKR*











*Only if you disconnect two plug leads on the XKR!

Did you know the Reliant Robin is faster to 30 mph than an XK8 under the same conditions.

I've not seen this fault before but have often found that seemingly random associated faults can often be down to a bad earth. It's the flashing brake light syndrome, one bad earth can affect a host of other systems. Might be worth a quick clean of all the body earths.
Good luck

OBD-II compliance has been compulsory in North America since 1996, but it wasn't brought in for UK/Europe until 2001, and 2004 for diesels. BUT - certain high-end vehicles, such as Jaguar (due in some part no doubt to the American "influence"...) were OBD-II compliant before this. My 1999 S-Type is, for example, and it is a U.K. spec car. So I'd say there is every happy chance that a 2000 XK8 is too.

Drag-STAAAHH!! ;o)

Wifi OBD2 Reader
 

Just got home and the OBD wifi reader for the iPad has arrived. As soon as I get some time I will try it on the car. I don't know what software you are supposed to use with this but I think it will be different to the Bluetooth reader which hasn't arrived yet.

Hopefully one of these will identify where the problem lies.

I will soon be burning off XKR's again!!!

I've got the Bluetooth blues
 

Set up the Bluetooth reader with Torque pro and it connected to the ECU without problem. however I can't seem to get any readings on stft's or ltft's. I go to real time then graphs then add display. The fuel trims all show in green but show a reading of 0% and if I click on this a graph just comes up with a spike reading 63% regardless of whether the engine is running or not. I am doing something wrong, what sort of readings should I expect at tick over and at 2500 rpm?

You have to have the engine running and warm so it goes into closed loop to see STFTs moving but you should see some offset on LTFTs -ie they will not both be at 0%.
Can you see any other live data like rpm?
I know the pro version of the app reads fuel trims correctly because I've used it.

Bluetooth can be fun!
 

The engine was warm and running but may not have been at full operating temp. The fuel trims at first were not reading but then they came up green but still only read 0% before opening them up as a graph. Once opened as a graph a green peak showed on the graph reading 63% but they all seemed to read this even with the engine not running and they didn't change at all with engine revs.

I don't fully understand how you are supposed to view the graphs as they all seem to open up on top of each other, must be something I am doing wrong. Lots of other data seems to be registering ok, the rpm goes up and down as you rev and it shows the engine temp etc. rising.

I will have another go, when I've got more time and hopefully will be able to get some readings.

First of all make some more pages for your graphs.
Press 'Menu' at the home screen Settings>General Preferences>Number of Dashboards
This gives you more blank pages in 'Realtime Information' to put your graphs on.
The spike to 63 followed by a fall to Zero is typical behaviour when not connected to the dongle.
Check your OBD settings in 'Settings'.

Fuel Trims
 

Tried again this afternoon to get a reading for the fuel trims but no joy. The scanner is definitely connecting to the ECU as I am getting numerous other readings. However when I go to fuel status it is telling me that the system is still open loop as engine temp too low!

However the engine had been running for over 20 mins and the reader was showing an engine temp of 97. I checked the O2 sensor readings and as I revved the engine both of them went from .01v to .09v which I believe is within range.

I thought it was these sensors that set the fuel system into closed loop, so I cannot understand why it is staying in open loop although I will be the first to admit that I know very little about modern engine electronics, well 13 year old engine electronics actually. Give me a dwell meter and a set of points and condenser and I would be in my element. Perhaps I should buy an old E type.

Does anyone out there know what is stopping the engine going into closed loop, perhaps this is what is causing my RP problem?

I don't like this.
You are stuck in open loop I'm sure.
To go into closed loop you need
Time
Coolant temp over something (I don't know what)
Output from the HO2 sensors.
Your ECM must be seeing the coolant hot and the time limit is only a couple of minutes so either the ECM is dead or your HO2S aren't reporting anything.
This could because they aren't getting a heating supply but I'd expect that to set a DTC.
They are fed by a common supply from the HO2S relay. If that wasn't working then that could be the problem.
If you look in the wiring diagram from JTIS, page 91, you'll see the colour coding is that you should have +12 on the white/green wires and the relay is the most inboard of the control module relays.
The fuse is no 1, 30A, in the engine management fuse box.
Hopefully the fuse or relay is duff.

Open the champagne
 

I don't believe it, quickly checked the fuses as suggested by Steve but could find nothing wrong. Also changed over the relay with another of the same type but again couldn't really see anything wrong, so just left it without trying the car.

Jumped in the car this morning and as soon as I turned on the ignition there were no lights or warnings and car revs freely. YA BA DABBA DO. I think the neighbours must have thought I was orgasming such was my delight with having got rid of the Restricted Performance.

Many thanks to you all, especially SteveinFrance who kept going right to the end with helpful suggestions. It just shows you what you can do if you persevere with a problem, although I must admit I was almost ready to hand the car over to a Jaguar specialist.

Next time I am touring France Steve, I will drop in a decent bottle of New Zealand wine, (only joking I love the French plonk really)

Anyway I am going to put the engine compartment back together now and take the car for a quick thrash. Fingers crossed that the fault won't return after a few miles! This is the first time that there has been no fault showing without clearing the fault on the reader so hopefully all will be well!

Just shows what can be done by using this Forum!

All the best

Jag U Are

Glad you're running again.
Do you think the relay was bad (in which case something else isn't working now!!) or just bad contacts?
Just to keep me happy can you see STFTs now?

Steve
 

Was wondering about the relay myself! Have just finished putting all the engine covers etc back on so am yet to find if something else isn't working. Hopefully it was just a bad connection. Will check the stft's after I have taken the car for a run and let you know what happens.

Once again many thanks Steve

Best Regards Rollo

Fingers crossed!

Don't uncross your fingers yet!
 

Still no RP yet but I am not convinced that the problem is completely solved. All rather strange, have done over 25 miles and the car absolutely flies with no hint of a misfire or lack of power.

However it worries me that it still shows the same fault codes as "pending". I am not quite sure if this means they are pending to go away or pending to come back! Even if I clear them down they still remain as pending.

Also the fuel status is still showing as open loop, even after the 25 mile run and an engine temp reading of 98c, it was showing low coolant temp as the reason for open loop.

So I really don't quite know what to believe at the moment, perhaps it is just a faulty reader. The car runs so well now that it is off RP that I can't believe that there is anything wrong with the fuel or injection system.

I think I will just have to take the car for a few more runs and see what happens


Que sera, sera as they say in Spain I think!