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I wonder if anyone can recognise these symptoms....
XJ8 3.2 Sport 1998 (Nikasil)
Car was effectively "laid up" so not used but started occasionally.
The dashboard lights started to flicker up and down in line with revs. which led me to think alternator problem causing voltage fluctuation. It was driving ok but then went into limp.
I had done work on replacing the dashboard bulbs a while before so I also considered a loose earth behind dash somewhere.
Then the fuel pressure went so car would not start which I concluded was fuel pump dying because fuel level was very low and that kills pumps (I now know).
I am in process of replacing pump and will then oil the bores and try to start after 4 years. My original problem is going to be there so I am looking for someone with experience of similar who may have the solution.
Video shows dash lights fluctuating and flickering
Your work on the IPK, retrace your steps as this is a major part of the CAN network, reseat the connectors on the bottom of the cluster. It could be a bent pin.
Alternator, check the voltage when running again. Earths, the engine earth connects at the rear of the block to chassis drivers side, undo, clean ends and refasten.
I oiled the bores and put in 3 gallons of fresh fuel and connected a fully charged battery. Checked everything and particularly the fuel pressure at the shrader valve. I had fuel!! Hooray so the new pump was working.
So turned the key and hey presto after a couple of revolutions she fired right up and ticked over really nice. I let her tickover for maybe 3 - 4 minutes while the oil circulated and quietened down a couple of noisy tappets. Then she stopped stone dead.
I had a horrible smell of hydrogen battery gas in the car so jumped out and checked the boot (trunk) expecting to see the battery fizzing and gassing but nothing untoward there it looked fine. Where was the smell from maybe the Cat??
So then I checked the shrader valve and no fuel. Pump has gone immediately.Back to square 1.
What is eating my pumps??
You could try jumping the fuel pump relay, first make sure the fuel pump fuse isn't burnt out then pull the relay and jump the two switched connections. Listen for a fuel pump noise to see if your pump's still going.
You could try jumping the fuel pump relay, first make sure the fuel pump fuse isn't burnt out then pull the relay and jump the two switched connections. Listen for a fuel pump noise to see if your pump's still going.
I jumped the relay and the pump does run. So something else is stopping the pump after it has pressurised. How long would it tick over with residual fuel pressure in the lines? If it is 2-3 minutes then that is what happened?
Another thought has crossed my mind and that is the pump has pushed off the hose in the tank. I think this because I can hear the fuel being pumped and "sloshing" inside the tank. It should not be making that noise unless it is a return line which runs a loop back to the tank? ? I guess I will check that the hose is secure before I go further.
Correct! The pipe was off the pump so reattached and made it really tight.
Starts up right away and settles to a decent idle. Now I smell the gas again so check battery voltage as I can see it bubbling in the SOC window. I am getting 18+ volts so no wonder the battery is gassing. It settles down to 17.5volts so still too high.
The fuel pump is buzzing loudly in the tank so not sure why?
Is it regulator or alternator? What to check next....
Many thanks
After 30 minutes idling
1. Battery voltage dropped to 15.5v. The battery is venting now. When I fitted a new battery I had battery acid in the trunk and blamed the battery but it looks like it is my charging systems fault.
2. The lights up on the dash are the red and orange with messages per the images attached.
3. The gearbox is stuck in Park. The P is illuminated. I can get out of Park via manual interlock button and all gears work but it jolts badly into reverse (it is in limp mode from before lay up - see above.) The Park was getting sticky previously so not surprised it no longer works.
The fault messages are sometimes irrelevant and random (not indicative of the real problem), for accurate investigation you need to plug in a code reader and get the trouble codes
Your work on the IPK, retrace your steps as this is a major part of the CAN network, reseat the connectors on the bottom of the cluster. It could be a bent pin.
Alternator, check the voltage when running again. Earths, the engine earth connects at the rear of the block to chassis drivers side, undo, clean ends and refasten.
Retraced steps and removed IPK but no signs of damage. I replaced one bulb which was out and replaced ensuring all pin connectors tight.
See my comments above on voltage (DC) at the battery.
I am having a difficult time finding the engine earth strap from above (right hand drive). Is it easier from underneath?
The fault messages are sometimes irrelevant and random (not indicative of the real problem), for accurate investigation you need to plug in a code reader and get the trouble codes
I ordered an OBD2 Scanner but seller advised the batch were faulty so offered a refund. I have a cheap OBD11 cable but no software so looking for that now. Not sure if the cable will work on the Jag.
It sounds like an iffy alternator to me, but glad you found the hose issue.
I don't like the sound of the reverse, that could be a trans problem, hard shifts are generally down to worn bores in the control valve assembly within the gearbox.
My advice at this point is to let it run at idle, but not driving, putting cycles through the electronics and alternator. It will do one of 2 things, either die, or level off to the 14.4V that you should be seeing. Overvolting and cooking batteries is a control diode on the back of the alternator expiring.
The other thing you should address is a small investment in the TransGo valve kit, plenty of threads on the ZF trans and it's issues/fixes - a quick search will pull up plenty of info.
The engine earth is indeed under the car, links the back of the block to the lower chassis and hard to miss once under there. While under there have a good look at freeing the gear selector, but don't disconnect it if possible. Plenty of penetrating oil/grease might help.
An OBD reader will give you engine codes, which you can post here.
"I don't like the sound of the reverse, that could be a trans problem, hard shifts are generally down to worn bores in the control valve assembly within the gearbox.
My advice at this point is to let it run at idle, but not driving, putting cycles through the electronics and alternator. It will do one of 2 things, either die, or level off to the 14.4V that you should be seeing. Overvolting and cooking batteries is a control diode on the back of the alternator expiring."
The jolting reverse happened after it went into limp mode caused by the electronic gremlins I suspect. I did exactly as you say leaving it in idle and going through the gears, switching on all the power/lights and checking voltages. The car moves forward and backwards. All the onboard systems appear to work. On a couple of occasions the gearbox did not jolt which would point to an electronic fault not a mechanical worn part in the box? Surely if the valve bore was damaged it would jolt every time?
I cannot drive on the road so it is just on my driveway.
I reckon if we identify the electronic fault the gearbox and limp mode will go away. I hope.
04-20-2017, 03:33 PM
Flickering dash lights and limp mode
