2010 Jag XK 5.0 Engine seems to be getting very hot
Discussion
I recently bought a 2010 XK 5.0 privately. Soon afterwards, I got the Restricted Performance and Engine Management Light on and what appeared to be some sort of misfire. I took it to the main dealer and they diagnosed one seized injector and fitted a new one. They tested the car extensively from hot and cold and assured me the problem was resolved.
After driving back from the main dealer and a couple of other short trips, I noticed that the engine seems to get extremely hot. The water level is up to the max and there are no signs of water loss (no leaks on the drive) and the oil level is also up to the max. I do get some white smoke at the start-up but I am assuming this is condensation and as far as I am aware, it clears once on the move. The car performs extremely well and there is no loss of power. The oil filler cap is very clean and has no signs of mayonnaise.
Looking at the dealer print-out from when they tested the car after fitting the injector, I see that the coolant temperature was 86 degrees celius on one test run and 96 degrees celius on the second test run. I'd imagine if they thought the car was running too hot they would have let me known, but can I just confirm if it is normal for this 5.0 litre engine to run so hot? It's the first 5 litre Jag I've owned so I'm not familiar with the engine. I keep reading horror stories on the Jag forums about the water pump and head gasket failing on this engine so am probably a bit paranoid about the engine overheating.
I'll keep a very close eye on the water and oil level everytime I use the car. I should add that the temperature gauge soon climbs to the mid way point and stays there - the temperature gauge has never gone past midway even when the engine seems very hot to me so maybe I'm over worrying but any advice greatly appreciated. I'm tempted to call the dealer that replaced the injector just to ask if such high running temperatures are normal for this engine.
After driving back from the main dealer and a couple of other short trips, I noticed that the engine seems to get extremely hot. The water level is up to the max and there are no signs of water loss (no leaks on the drive) and the oil level is also up to the max. I do get some white smoke at the start-up but I am assuming this is condensation and as far as I am aware, it clears once on the move. The car performs extremely well and there is no loss of power. The oil filler cap is very clean and has no signs of mayonnaise.
Looking at the dealer print-out from when they tested the car after fitting the injector, I see that the coolant temperature was 86 degrees celius on one test run and 96 degrees celius on the second test run. I'd imagine if they thought the car was running too hot they would have let me known, but can I just confirm if it is normal for this 5.0 litre engine to run so hot? It's the first 5 litre Jag I've owned so I'm not familiar with the engine. I keep reading horror stories on the Jag forums about the water pump and head gasket failing on this engine so am probably a bit paranoid about the engine overheating.
I'll keep a very close eye on the water and oil level everytime I use the car. I should add that the temperature gauge soon climbs to the mid way point and stays there - the temperature gauge has never gone past midway even when the engine seems very hot to me so maybe I'm over worrying but any advice greatly appreciated. I'm tempted to call the dealer that replaced the injector just to ask if such high running temperatures are normal for this engine.
Edited by hal3210 on Saturday 30th March 14:07
hal3210 said:
I recently bought a 2010 XK 5.0 privately. Soon afterwards, I got the Restricted Performance and Engine Management Light on and what appeared to be some sort of misfire. I took it to the main dealer and they diagnosed one seized injector and fitted a new one. They tested the car extensively from hot and cold and assured me the problem was resolved.
After driving back from the main dealer and a couple of other short trips, I noticed that the engine seems to get extremely hot. The water level is up to the max and there are no signs of water loss (no leaks on the drive) and the oil level is also up to the max. I do get some white smoke at the start-up but I am assuming this is condensation and as far as I am aware, it clears once on the move. The car performs extremely well and there is no loss of power. The oil filler cap is very clean and has no signs of mayonnaise.
Looking at the dealer print-out from when they tested the car after fitting the injector, I see that the coolant temperature was 86 degrees celius on one test run and 96 degrees celius on the second test run. I'd imagine if they thought the car was running too hot they would have let me known, but can I just confirm if it is normal for this 5.0 litre engine to run so hot? It's the first 5 litre Jag I've owned so I'm not familiar with the engine. I keep reading horror stories on the Jag forums about the water pump and head gasket failing on this engine so am probably a bit paranoid about the engine overheating.
I'll keep a very close eye on the water and oil level everytime I use the car. I should add that the temperature gauge soon climbs to the mid way point and stays there - the temperature gauge has never gone past midway even when the engine seems very hot to me so maybe I'm over worrying but any advice greatly appreciated. I'm tempted to call the dealer that replaced the injector just to ask if such high running temperatures are normal for this engine.
Why do you think that it is getting hot if the temperature gauge says it is normal? Relax dude!After driving back from the main dealer and a couple of other short trips, I noticed that the engine seems to get extremely hot. The water level is up to the max and there are no signs of water loss (no leaks on the drive) and the oil level is also up to the max. I do get some white smoke at the start-up but I am assuming this is condensation and as far as I am aware, it clears once on the move. The car performs extremely well and there is no loss of power. The oil filler cap is very clean and has no signs of mayonnaise.
Looking at the dealer print-out from when they tested the car after fitting the injector, I see that the coolant temperature was 86 degrees celius on one test run and 96 degrees celius on the second test run. I'd imagine if they thought the car was running too hot they would have let me known, but can I just confirm if it is normal for this 5.0 litre engine to run so hot? It's the first 5 litre Jag I've owned so I'm not familiar with the engine. I keep reading horror stories on the Jag forums about the water pump and head gasket failing on this engine so am probably a bit paranoid about the engine overheating.
I'll keep a very close eye on the water and oil level everytime I use the car. I should add that the temperature gauge soon climbs to the mid way point and stays there - the temperature gauge has never gone past midway even when the engine seems very hot to me so maybe I'm over worrying but any advice greatly appreciated. I'm tempted to call the dealer that replaced the injector just to ask if such high running temperatures are normal for this engine.
Edited by hal3210 on Saturday 30th March 14:07
Many thanks for the replies. You are right about relaxing! I know I must sound mega paranoid suspecting water pump or head gasket trouble when the oil and water levels are 100% fine and the temp gauge is in the middle! I should stop reading up on the worst case scenarios of this engine on the Jag forums!
With out any other signs of there being an issue other than you thinking the engine seems hot, I wouldn't worry too much! 
I had a 4.0 S/C XKR before, and now have a 2010 5.0 S/C XKR and a 5.0 S/C Range Rover. The Jag engines do seem to kick out a lot of heat, more so than I've noticed on the RR. I always thought the amount of heat coming of the older 4.0 (XK100 model) was excessive, under the bonnet was almost scalding hot to touch bits after a run, and the 5.0 I have now is not quite so bad but is still hot when you've parked up.
Just keep an eye on your water usage , and the temp gauge for a few weeks, you'll soon stop worrying about it.
ETA: The water pump on the Jag has been fine (it's on 96k miles now), but the RR engine did s
t it's pump a few thousand miles back (now on 106k miles). Symptons of pump going were slight loss of water of a few hundred miles of usage across a couple of weeks, then virtually catastrophic failure/disintegration of pump bearings on a drive down the M4. I did get 2 low level warnings in the weeks leading up to the failure so should have checked things sooner, but thought I'd have a bit more time to get it fixed.
Lesson: if your 5.0 engine starts using water... get the pump checked double quick!
I had a 4.0 S/C XKR before, and now have a 2010 5.0 S/C XKR and a 5.0 S/C Range Rover. The Jag engines do seem to kick out a lot of heat, more so than I've noticed on the RR. I always thought the amount of heat coming of the older 4.0 (XK100 model) was excessive, under the bonnet was almost scalding hot to touch bits after a run, and the 5.0 I have now is not quite so bad but is still hot when you've parked up.
Just keep an eye on your water usage , and the temp gauge for a few weeks, you'll soon stop worrying about it.
ETA: The water pump on the Jag has been fine (it's on 96k miles now), but the RR engine did s
t it's pump a few thousand miles back (now on 106k miles). Symptons of pump going were slight loss of water of a few hundred miles of usage across a couple of weeks, then virtually catastrophic failure/disintegration of pump bearings on a drive down the M4. I did get 2 low level warnings in the weeks leading up to the failure so should have checked things sooner, but thought I'd have a bit more time to get it fixed. Lesson: if your 5.0 engine starts using water... get the pump checked double quick!
Edited by Piersman2 on Saturday 30th March 16:39
Many thanks for the reply Piersman2. I think I've finally put my mind at rest! It's interesting to hear that the Jag engine kicks out more heat than the RR. I've never had a 5 litre Jag before so I was quite alarmed by how hot the engine becomes but it's good to hear that this is normal for this engine. If anything, I'd have more to worry about if the engine was too cold!
I had an early non supercharged 4.0 XK8 many years ago that had covered 160,000 miles - I don't recall that engine getting especially hot but I was probably less of a worrier back then! These forums are really good but it's all too easy to over research cars and to read about worst case scenarios.
As you say, I'll keep an eye on the water and the temperature gauge but I'm sure I'm worrying over nothing. I think I'm right in saying that if the water and oil levels are 100% it's highly unlikely there is anything wrong with the head gasket of water pump.
I'm sorry to hear about your RR - it's definitely worth checking the water levels regularly. I won't be doing any long journies so I can literally check the water every few miles. To be honest, years ago I wouldn't have checked the water levels from one year to the next but I think with the 5.0 I will literally check the water every few days, as paranoid as that must sound! The Jag I have is on 76k miles, its full Jag service history but just a stamped book rather than any bills. I have been thinking of calling the servicing dealer to see if they've done a water pump in the past but I'm probably thinking about this too much really!
I had an early non supercharged 4.0 XK8 many years ago that had covered 160,000 miles - I don't recall that engine getting especially hot but I was probably less of a worrier back then! These forums are really good but it's all too easy to over research cars and to read about worst case scenarios.
As you say, I'll keep an eye on the water and the temperature gauge but I'm sure I'm worrying over nothing. I think I'm right in saying that if the water and oil levels are 100% it's highly unlikely there is anything wrong with the head gasket of water pump.
I'm sorry to hear about your RR - it's definitely worth checking the water levels regularly. I won't be doing any long journies so I can literally check the water every few miles. To be honest, years ago I wouldn't have checked the water levels from one year to the next but I think with the 5.0 I will literally check the water every few days, as paranoid as that must sound! The Jag I have is on 76k miles, its full Jag service history but just a stamped book rather than any bills. I have been thinking of calling the servicing dealer to see if they've done a water pump in the past but I'm probably thinking about this too much really!
The other way to look at that situationis that the engines are designed with less mass and better heat dissipation so that they get rid of the excess heat into the engine bay instead of trapping it inside the engine and making the cooling system work harder. The specific power output is probably higher too (more power out of a smaller engine).
I'm also confused about why you are thinking it is getting hot. Is it the heat when you open the bonnet or how hot the bonnet gets as opposed to what is being indicated on the gauges?
If so, what you are seeing is most likely just the result of stuffing a big engine under a low bonnet line.
If so, what you are seeing is most likely just the result of stuffing a big engine under a low bonnet line.
Thanks again for the replies. Am I right in thinking that the seized injector when I bought the car would have made it run colder? I see that the main dealer print out that tested the car when the injector was seized showed a coolant temp of 86 degrees Celsius and 96 degrees Celsius when the injector was replaced. So I've probably noticed that the bonnet and grille area seems a lot hotter than it was prior to the new injector.
I know I'm best to stop worrying unless the temperature gauge goes above the mid point. It's good to hear that 96 degrees isn't hot for a modern engine.
I know I'm best to stop worrying unless the temperature gauge goes above the mid point. It's good to hear that 96 degrees isn't hot for a modern engine.
Replaced the water pump (amongst other things) on my xjss at 94k miles. Normally the bearings fail and make a racket first and you can see the pulley vibrating about.
Mine didn't overheat at all despite the bearings having failed.
I also did a lot of work on it with a warm engine and there is a lot of motor in there generating heat! 96 degrees is no problem on a pressurised system.
Mine didn't overheat at all despite the bearings having failed.
I also did a lot of work on it with a warm engine and there is a lot of motor in there generating heat! 96 degrees is no problem on a pressurised system.
Just to update this thread, I have now obtained all the previous service and repairs receipts for the car and when the last owner took the car in to get the same misfire/Restricted Performance light diagnosed, his main dealer diagnosed the following:
"Investigated report of customers concern of misfire. Carried out fault code read, cylinder block test, no compression in the engine, coolant pressure test, confirmed new heads required."
It seems very strange that the Jaguar main dealer I took the car to diagnosed and cured the car with a new injector yet the other Jaguar main dealer thought the car needed new heads!
Yesterday though, I had another problem with the car - it lost all its coolant water very rapidly and I assumed this was because of the water pump and / or crossover pipe failing. I checked the oil cap and there was no mayonnaise and the oil level is still fine. The coolant was clean and not contaminated.
So am I right in thinking this rapid water loss is probably not related to head failure?
Greatly appreciate any advice on this - I guess I need to get the car compression tested myself but as I say, once the new injector was fitted the engine performed perfectly - surely if there was no compression in the engine a new injector would not cure this. What's strange though is that the car was driving 100% fine, surely if there was no compression in the engine, performance would be terrible.
"Investigated report of customers concern of misfire. Carried out fault code read, cylinder block test, no compression in the engine, coolant pressure test, confirmed new heads required."
It seems very strange that the Jaguar main dealer I took the car to diagnosed and cured the car with a new injector yet the other Jaguar main dealer thought the car needed new heads!
Yesterday though, I had another problem with the car - it lost all its coolant water very rapidly and I assumed this was because of the water pump and / or crossover pipe failing. I checked the oil cap and there was no mayonnaise and the oil level is still fine. The coolant was clean and not contaminated.
So am I right in thinking this rapid water loss is probably not related to head failure?
Greatly appreciate any advice on this - I guess I need to get the car compression tested myself but as I say, once the new injector was fitted the engine performed perfectly - surely if there was no compression in the engine a new injector would not cure this. What's strange though is that the car was driving 100% fine, surely if there was no compression in the engine, performance would be terrible.
Unless it dumped all it's water on the ground or boiled it all off in a cloud of steam it must have gone through the engine. People always say 'head gaskets' but in reality there's always the potential of cracked block/head etc.
I would suggest you carry out a chemical test of the coolant. They're not always conclusive but unless the leak is very small you'll get your answer. Mayo' (or lack of) under the filler cap is a poor indicator. I've had combustion gasses in the coolant with perfectly clean oil on many occasions.
I would suggest you carry out a chemical test of the coolant. They're not always conclusive but unless the leak is very small you'll get your answer. Mayo' (or lack of) under the filler cap is a poor indicator. I've had combustion gasses in the coolant with perfectly clean oil on many occasions.
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