Hello everyone !

I got a 1996 X300, 3.2L (french specs), which is running very poorly, with a very bad iddle.

The seller made a diagnosis at jaguar that stated the 02 sensors and the ECU were faulty.

I changed the 2 02 sensors with OEM ones (a steal !) and it did not change anything.

The seller supplied me a spare ECU from a 95 XJR, in good running order.

So, here are my questions:

1. If I swap the ECUs, will I have to do a form of remap or reset at jaguar garage ?
2. Will the car start ? (I believe there is a form of "smart" key in these cars)
3. Do you think it is likely to solve the issue or not ? To my mind, it sounds rather like a fuel injection issue or an ignition one....
4. Finally, if it is not the cause of the problem, can I go back to the original ECU ?

Thanks a lot for your help

Julien

 

It is unlikely a XJR ECU will work in your car. Before you swap I would suggest you have an independent specialist check the car out. The dealers have a general practice of throwing parts at cars when they aren't sure what is wrong.

 

If you do attempt the ECM swap I suggest you also swap the 2 PROMS on the circuit board to ensure that the correct software remains with the engine.

I know nothing of 3.2 because the North American market has NO 3.2 engines. Only 4.0.

bob gauff

 

Thanks for the answers !

Basically, the 3.2l engine is the same as the 4.0l one, but was made for some markets for fiscal reasons (France, Spain...). Everything else is the same as the 4.0l one.

What are the the 2 PROMS on the circuit board ? Where are they located ?

The seller only supplied me the ECU/ECM and nothing else.

But I am not sure at all that the ECU is faulty. I will probably investigate further options before swaping ECUS

Julien

 

Here is some info on the PROMS.
This is for the North American market but swapping the PROMS info is in there.

bob gauff

 

Thanks for the help !

I came across this guy and it seems ther is no need for a remap or PROMS swap, provided you have the right ecu.

Jaguar XJ6; Jaguar X300; Engine Control Unit; ECU

By the way, I will investigate that deeper this week end and keep you updated !

 

You stated that you were going to install a SUPERCHARGED ECM into a Normaly Aspirated 3.2 car.

I told you to swap the PROMS if you were going to try this!!!!!!!!!!!!!!!!

You can certainly get a correct ECM and that should work without modification.

The TPS 'might' not be calibrated to the replacement ECM. That is why I thought it might be better to use the original PROMs from the car. The original PROMs might still have the correct setup??

good luck.

bob gauff

 

Dear all !

Thanks for the comments and replies ! Indeed, I did not think about the supercharger of the XJR version... Might have to check but it is written it is for a 3.2L. But there were only 4.0L supercharged engines. Quite strange...

But this is not the most interesting :-)

I have beebn investigating the ignition. It revealed that ignition coil on cylindre N°2 was very small and appeared quite randomly.

I believed I found the culprit but it wasn't... Tonight I changed the ignition coil and the issue is still the same. The engine seems to run better without the ignition coil plugged on cylindre N°2.

I am not sure oof what to do next ... I doubt it is a wiring harness issue. So what is attached beyong it ? The ECU...

Do you have any other ideas ? All coments and ideas are welcome !

Best regards
Julien

 

Hi all !

Finally, I have tried to swap both ecus as they are exactly the same, and .... it did not change anything !

It is even worse since the iddling is even worse. So I went back to the original and it is a bit better.

I will open a new tread with complete desciption of symptoms and what I did on the car.

Thanks for the help !
julien