217 is (was) too hot.

As I recall it's only the V6 that can do the heat-saving cylinder shut-down stuff.

It's due to having CHT sensor(s) that the V8 does not have - I think.

It's certainly odd it didn't flag a code, though I'm not sure what code is available.

 

On the LS yes. You will have the limp home symbol and "Fail Safe" message in the message center on the dash and it should set a over temperature code too. It's pretty cool how it works. From the Ford service manual;

Fail-Safe Cooling Strategy
Only vehicles that have a cylinder head temperature (CHT) sensor will have the fail-safe cooling strategy. This strategy is activated by the PCM only in the event that an overheating condition has been identified. This strategy provides engine temperature control when the cylinder head temperature exceeds certain limits. The cylinder head temperature is measured by the CHT sensor. For additional information, refer to PCM Inputs for a description of the CHT sensor.

A cooling system failure such as low coolant or coolant loss could cause an overheating condition. As a result, damage to major engine components could occur. Along with a CHT sensor, a special cooling strategy is used to prevent damage by allowing air cooling of the engine. The vehicle can be safely driven for a short time with some loss of performance.

Engine temperature is controlled by varying and alternating the number of disabled fuel injectors. This allows all cylinders to cool. When the fuel injectors are disabled, their respective cylinders work as air pumps, and this air is used to cool the cylinders. The more fuel injectors that are disabled, the cooler the engine runs, but the engine has less power.

Note: A wide open throttle (WOT) delay is incorporated if the CHT temperature is exceeded during WOT operation. At WOT, the injectors will function for a limited amount of time allowing the customer to complete a passing maneuver.

Before injectors are disabled, the fail-safe cooling strategy alerts the customer to a cooling system problem by moving the instrument cluster temperature gauge to the hot zone. Depending on the vehicle, other indicators, such as an audible chime or warning lamp, can be used to alert the customer of fail-safe cooling. If overheating continues, the strategy begins to disable the fuel injectors, a DTC is stored in the PCM memory, and a malfunction indicator light (MIL) (either CHECK ENGINE or SERVICE ENGINE SOON), comes on. If the overheating condition continues and a critical temperature is reached, all fuel injectors are turned off and the engine is disabled.

 

Exactly. Only the 3.0 has CHT(s) as I recall.

Er... I think the CHTs were deleted with the 2002.5MY (2003 USA) and on

That's when jag moved to the Denso PCM. Maybe the LS stuck with the former (Ford PTEC/PTECH/PCM150) PCM.

 

Yes +1 on the 3.0 - when my 4.0 overheated (seized fan motor) I received the excessive engine temperature message on the cluster but no shut down. Of course I pulled over and shut her down immediately...

Glad you're up and running..

 

And so the plot thickens... I was just reading through a factory training manual (2000-2002 Student Guide T870B) and it confirms only the 3.0 V6 had the Cylinder Head Temp (CHT) switch and the corresponding overheat limp-home strategy. So this thread would make perfect sense if the subject engine was a 3.0 V6, but it's a 4.0 V8.

Glad it's fixed, but I'm still as confused as ever.

 

Yes the Lincoln LS info I posted might have confused things even more. There are differences.
Sorry about that.
.
.
.

 

This forum/post has been incredibly insightful. I had issues about 6 months ago (traction control/stability blah blah). Ended up swapping out the TB which seemed to cure the issue but then had some bad idle problems. To cut a very long story short I swapped plugs, MAF, air filter, BOTH O2 sensors and finally cleared all the cods except for the bad idle which as luck would have it was actually a disconnected breather hose (which I must have knocked off whilst swapping out the plugs. BUT, I now have a new issue where I can drive about 5-10 miles, she coughs, splutters and eventually dies. Key out, count to 5, key in and off she goes for another few miles - and repeat.
I will be checking for fuel pressure, swapping out the fuel filter and where I had to remove the water expansion tank to get to the Bank 2 O2 sensor I will be checking for air in the coolant.
Wish me luck
Kev

 

Be sure and post back if you find the solution. If not post how far you got. It will help the next guy maybe.
.
.
.

 

My last issue was that she would run for about 10 mins then cough and splutter and lose all power. Gunning the throttle drowned it like she was flooding. Immediately resolved with a restart of the ignition. Then go for another couple of miles
Tonight, the only thing I did was squirt the Schroeder valve to confirm I had fuel pressure, shy of that I drove around for an hour without any issues at all. Please Lord let that be the end of my gripes !! I'll venture out further tomorrow and see how it goes.
So, to date, 2 x new O2 upstream lambda sensors ( I wonder if they needed time to 'burn' in?)
New MAF sensor - didn't make a blind bit of difference so put the old one back in.
New throttle body - different issue and it was the initial problem. Watching this indicated that I had exactly the same issues and fault codes.
Prior to that I had part serviced here with plugs, and air filter. Oil and filter are still to be done.
I also let her idle until the fans kicked in to see if it was an overheating issue but she was fine all night.
Kev

 

Full episode.....mine's the same colour but doesn't have the BBS alloys.

 

What does OBD live data show? It can tell you so much .... if you use it.

 

Ha ha...tried using it tonight and nearly took her into a ditch looking at it on my Android. I need to pay for the full version and try again. :-)

 

You could do a lot when parked.

 

Bad fuel pump

 

Do you know what I think the final issue was? Stale fuel. I took her out last night for a burn and then in to work this morning (20 miles0 and she never missed a beat. 30 ltrs of fresh fuel and another burn and she's running beautifully.
As someone quoted on the site 'if your Jag is running well, then something is about to break imminently' so we'll see what problem we get next.
I'd like to thank all the contributors to this post for the guidance and pointers. Looks like you all went through the grief on my behalf.
I'm now a happy motorist (for now) :-)
Kev

 

That's awesome. A bit of advice. Don't run your car with less than 1/2 tank of fuel. Low fuel levels will definitely fry the fuel pump.

 

Aaaaaargh !!! On the way home in the glorious sunshine, lid down, the tonneau cover came loose and caught on the aerial snapping in in two and scratching the boot/trunk lid. Grrrrrrr!!
Jinxed.