Ford MK4 '93 epic fault code

[Miner2900]

Hi, I have a Ford Transit from 1993 with lucas epic pump.
EML light remain on after crank, using the paperclip trick the blink the EML light show code 12, 41, 11.
After resetting the code the code reappears if i start the engine again.
Anyone know what could be the issues?

[MinorMatt]

12 - Start of Codes
41 - Crankshaft Position Sensor
11 - End of codes

[Miner2900]

Ok thanks, I tried cleaning the contact of the crankshaft sensor because it has some dirt and corrosion but nothing error still persist (obviously I deleted the error before test again) , I'll try replacing it with a new one. Now there is another persistent code 54 beyond 41, sometimes show up code 34. The engine shut off after 3 - 4 seconds when the l turn the ignition to off position.

[MinorMatt]

Ahh if it runs on the stop solenoid plunger needs replacing - this will put it in to limp mode. (thats code 54)

In the short term, stall it as you switch it off (i.e. at the same time as turning the key)

[Miner2900]

I've had problems with the the solenoid 6 months ago when I switched from bulb to led the brake light, with position lights off and brake pedal pressed engine don't shut off due to a lack of a diode to prevent current flowing from position lamp to whatever supply the lamp. Could the solenoid has been damaged due to this problem?
Because it seem strange the problem suddenly pop out.

[Miner2900]

Hi crankshaft position sensor replaced but problem still persists, every time I shut off the engine the blink code show 54, 34, 41. If I stall the engine when I turn the key off there are no error, the solenoid could cause all the error?

[MinorMatt]

Yes. New plunger needed

[marcrbarker]

When replacing the plunger round the back of the injector pump , beware of a tiny little O ring than can jump out un noticed and cause really weird effect and major headache I wrote about it on a previous thread.
viewtopic.php?f=4&t=209552&start=15#p1746282

[Miner2900]

I replaced the solenoid plunger, now the engine shuts down correctly so this problem is solved.
Thanks marcrbarker for the suggestion, luckily the little o ring was in place during reassembly.
The error code 41 still persist; I have already replaced the Crankshaft Position Sensor, the cable is not damaged and the connection on both side is good, the EML light rarely shut off but error 41 is still presesnt. Any suggestion?

[marcrbarker]

This is curious, interpreting between the lines
Am I correct in saying, the engine light on and paperclip blink codes (12) 41 (11) code (crank sensor circuit),,,, this has been for many months, a year?

The engine starts and runs OK I presume. (?with crank sensor code)

Also am I correct in saying: that at the same time you changed standard light bulbs for LED ones,,, is also when the engine first began to 'run on' for a few seconds after turning off the key? and that having the lights on and/or brake pedal pressed seemed to have an effect on the 'running on'? I guess you attributed something to do with the changed light bulbs was the cause. (After you replaced the solenoid plunger this stopped, and so did the other 2 blink codes).

Now you are back to (12) 41 (11) blink codes. After clearing it they come back when engine started. Engine light on. You replaced the crank sensor and you checked the connections at both ends.

Some ideas. Retest the connections again. Leave the crank sensor plugged in. Measure the resistance of the crank sensor at the connector to the engine management ECU end. To the crank sensor wires. It is a screened twisted pair of wires, (I believe the screen is only connected at the ECU end). You should see the resistance of the sensor, a few hundred ohms.
You leave the tester connected then flex and manipulate the harness and see if the resistance reading jumps.
If you want to see the crank sensor doing something, then crank the engine while the resistance tester is still connected, you will see the resistance reading fluctuate.

[Miner2900]

The problem pop out many year ago and the engine light rarely remains on, gradually the the light stays on more and more often so I checked the blink code recently when the engine light remain always on. I tried measuring the sensor from the ECU connector and directly on the sensor connector, I get the same value but I do not tried moving the cable during measure. In the schematic the shielding should be connected to pin 27 of the ECU but this pin seems to not be connected on power or ground.

[marcrbarker]

In the schematic the shielding should be connected to pin 27 of the ECU but this pin seems to not be connected on power or ground.

Of the two wires of the crank sensor, the sheild/screen 'braid' around these two wires, is only connected at the ECU end (pin 27).
At the sensor end of the cable, the screen must not be connected to anything , It must be insulated.

[Miner2900]

I measured the shielding and the connection to pin 27 is good

[Miner2900]

After some test the ecu seems to be the only thing that can cause the issues, I'm searching for a replacement; I found a seller who has some ECU in Europe but it say the ECU need "adaptation by IDS Ford Device".
Correct me if I'm wrong, the MK4 should not have the immobilizer so an ECU from another truck should work without any "adaptation" and with the info I have the IDS Ford interface work only from year 1996.

[MinorMatt]

a Mk4 ECU (92VB part number) will not need coding to the vehicle. It should be plug and play