P38 '95 4.6 misfire

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Quick update, seems its the ECU not switching.
Option one; get current ECU checked at cost of £35 with worst case extra £160 so possible £195.
Option two; Buy tested used unit from fleabay for £29.50 free delivery.

So, its Option two then.

Let you know if it works,,,,,,,,,,,,,,,,,,,,,,:rolleyes:
 
maelstrompat said:
Quick update, seems its the ECU not switching.
Option one; get current ECU checked at cost of £35 with worst case extra £160 so possible £195.
Option two; Buy tested used unit from fleabay for £29.50 free delivery.

So, its Option two then.

Let you know if it works,,,,,,,,,,,,,,,,,,,,,,:rolleyes:
Click to expand...

If you want to try one first, I've got a spare ECU you can try, cost you the post to you and back.

NNN100470 99 Date Code. Edit : Ignore it, yours is too early! :eek:

Peter
 
Last edited:
OK, very good delivery service from Black Country 4x4, arrived today by DHL.

Problem is, they have sent a 4.0 litre ECU and mine is a 4.6.

From an earlier post (28 June 2011) from Irishrover:

"Theoretically, the GEMS will recognise any code between 0 and 65535.
The majority of GEMS codes are 65535 so there is a chance it may be a straight swap if both are set at 65535. However I have come across ECUs with 0.
Hence my suggestion that having someone standing by with the diagnostic system to do a re-learn, if required, when they are swapped over".

My question is;

How can I find out what codes apply to my 4.6 ECU and the 4.0 ECU?
Are the codes listed anywhere on the vehicle or is it a case of plug it in and the dianostics will find out?
Both part numbers are identical.
 
I believe that the ECU, same as the later Bosch one, contains both engine maps, it certainly seems that way on Microcat.

Here are the options:

P38ECU.jpg


Peter
 
First of all where are you ?
Misfires can be caused by loads of causes.
Wasted spark coils MUST have both plugs earthed to the engine, otherwise the spark can back feed into the ecu. I use a new plug and a medium croc clip and a jubilee clip. Screw the jubilee clip around the plug and the croc clip. That way you can earth the test plug and observe the colour of the spark. Do not do a old fashioned spark strength test. (holding the lead away from a head to see how far the spark jumps. 1/ you could kill yourself 2/ the back emf will screw the electronics. The voltages without looking at the diagram should be present at one side of the coil and switched on by the ecu to earth. It has been known to have corrosion on the wiring loom and it is possible that is the solution. look at the diagram and assess the right side for the voltage. it should be there so you could try a fused jumper to provide the 12v. BUT do assess the right feed before doing this.
 
tnseal said:
First of all where are you ?
Misfires can be caused by loads of causes.
Wasted spark coils MUST have both plugs earthed to the engine, otherwise the spark can back feed into the ecu. I use a new plug and a medium croc clip and a jubilee clip. Screw the jubilee clip around the plug and the croc clip. That way you can earth the test plug and observe the colour of the spark. Do not do a old fashioned spark strength test. (holding the lead away from a head to see how far the spark jumps. 1/ you could kill yourself 2/ the back emf will screw the electronics. The voltages without looking at the diagram should be present at one side of the coil and switched on by the ecu to earth. It has been known to have corrosion on the wiring loom and it is possible that is the solution. look at the diagram and assess the right side for the voltage. it should be there so you could try a fused jumper to provide the 12v. BUT do assess the right feed before doing this.
Click to expand...
Thanks for your response. Interesting info. I'm from Exeter, Devon.
Pat
 
Thanks Peter, I understand. Should know tomorrow if it is the ECU, if not ~ coil out to see if its burnt. Also, check wiring for corrosion.

Pat
 
OK, fitted the 4.0 litre ECU and it started and ran perfectly ~ congratulations all round but then I tried to re-start but no joy.:D

We know that an ECU is required but the 4.0 litre has to be re-mapped at a cost of £80 + VAT (Is that about right?)

I have emailed Black Country 4x4 to see if they have a 4.6 ECU and if so, would they do a swap.
 
If the engine started OK, it should start again, unless there is some security block inside the ECU etc that stops the ECU from another vehicle being used? I think there is something like that on the D2's.

It isn't remapping the ECU as such, it is changing the map that the engine uses from the 4.0 to the 4.6 inside the ECU as far as I can see, there isn't a separate ECU that is listed for each engine, as per the table I posted the other day.

It's the same with the Thor engine ECU, both engine maps are in there, you just have to switch between them.

I'd be interested to see what Black Country come up with.

Peter
 
listerdiesel said:
If the engine started OK, it should start again, unless there is some security block inside the ECU etc that stops the ECU from another vehicle being used? I think there is something like that on the D2's.

It isn't remapping the ECU as such, it is changing the map that the engine uses from the 4.0 to the 4.6 inside the ECU as far as I can see, there isn't a separate ECU that is listed for each engine, as per the table I posted the other day.

It's the same with the Thor engine ECU, both engine maps are in there, you just have to switch between them.

I'd be interested to see what Black Country come up with.

Peter
Click to expand...

Peter

Thanks, you said "It isn't remapping the ECU as such, it is changing the map that the engine uses from the 4.0 to the 4.6 inside the ECU as far as I can see....................you just have to switch between them"

So, how would the switching be achieved, would it still need to be re-mapped?

Pat
 
maelstrompat said:
Peter

Thanks, you said "It isn't remapping the ECU as such, it is changing the map that the engine uses from the 4.0 to the 4.6 inside the ECU as far as I can see....................you just have to switch between them"

So, how would the switching be achieved, would it still need to be re-mapped?

Pat
Click to expand...

I guess that it would be done in Testbook, unless Nanocom or Hawkeye can do it.

Forget the remapping bit, think 'change of engine maps'.

RAVE states that the D2 ECU has both 4.0 and 4.6 'Tunes' as they call them in the memory, and I'm pretty certain the same goes for your engine.

I haven't got the right RAVE copy for your car, I'll see if I can pick it up on the web.

Peter
 
UPDATE

Really impressed with service Blackcountry 4x4 are giving, emailed Lisa and she is sending me a 4.6 ECU and I am returning the 4.0 litre one.

It makes a pleasant change to find a Company like Blackcountry 4x4 who appear to have good old fashioned levels of service! Well Done to them!

This one's for Lisa.............:)

Business seller information


Blackcountry4x4

Unit B, Woodside Industrial, Pedmore Road
Dudley
West Midlands
Dy2 0RL
United Kingdom


Phone:01384 484853
Email:[email protected]
 
Great service from Blackcountry 4x4 again (no I don't own shares!) but: New (s/h) 4.6 ECU arrived today. Fitted and engine would not start. re-fitted old one and engine starts (with misfire as usual), tried three times but same result. Not sure what to try next.
 
Final Update!
"Oh what a beautiful morning!"
Can't believe its sorted ~ Beacon Garage of Ottery St. Mary called around with their Auto-Logic, swopped over the ECU as supplied by Blackcountry 4x4 and all 8 cylinders started singing!
Now the Oscars:clap2: ~ I would like to thank all those who contributed to this thread including private messages.
Lesson is; P38 ECUs do give up the ghost and before you wrestle with removing the GEMS coil ~ get your ECU checked out.:)
 
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