2017 Transit Custom 2.0 EcoBlue – hot restart problem(p0341)

[WhoThatCar]

Hi,

I have a 2017 Ford Transit Custom 2.0 EcoBlue with manual transmission and approximately 106,700 km.

The vehicle has recently been remapped to approximately 185 hp, with:

- EGR delete
- DPF delete
- AdBlue delete

After the new remap, the vehicle started displaying fault codes again. It is possible that the previous software was hiding or disabling some fault codes.

Main problem

The engine starts normally when cold.

When the engine is warm, usually above approximately 50°C, it often fails to restart correctly.

During a failed restart:

1. The starter cranks normally.
2. The engine fires and reaches approximately 900–1,100 rpm.
3. It runs for around one second.
4. The rpm drops and the engine dies.
5. The dashboard displays:

“Auto Start Stop – Manual Restart Required”

If the engine stays running, it drives and idles normally. It never cuts out while driving.

Rail pressure is above approximately 250 bar during hot cranking, so it appears to have enough fuel pressure.

Fault code

The PCM repeatedly stores:

P0341 – Camshaft Position Sensor A Circuit Range/Performance

The code returns after being cleared, even when the engine starts normally from cold.

FORScan normally shows:

- Cam/crank synchronization: On
- CMP status: No Fault
- Fuel enable: Yes

The P0341 code has previously been recorded with both low cranking voltage and normal charging voltage, so low battery voltage does not appear to be the only cause.

Parts already replaced

The following parts have been replaced without changing the problem:

- Genuine Ford camshaft position sensor
- Crankshaft position sensor
- Ignition switch
- Fuel rail pressure sensor
- Diesel fuel filter
- One injector, correctly coded

The genuine Ford camshaft sensor made no difference.

Camshaft sensor wiring

The sensor has three wires:

- Green/brown: approximately 5 V supply
- Purple: sensor ground
- Brown/grey: camshaft signal

Measured values appear normal with a multimeter:

- Supply: approximately 5.0 V
- Ground: close to 0 V
- Signal: approximately 4.9 V with the engine stopped and 2.2–2.4 V average when running

However, a multimeter cannot show missing or incorrectly timed signal pulses.

Ground and starter testing

Voltage drop between battery negative and the engine/starter housing was approximately:

- 0.62 V through the original ground path
- 0.32 V with a jump lead directly from battery negative to the engine

I have added an extra ground cable between the engine/gearbox and the body.

The voltage drop is similar when the engine is cold and hot, so I am not sure it explains why the restart problem only happens when warm.

There is also an occasional separate issue after the vehicle has been parked overnight. On the first start attempt, the starter sometimes appears to spin without properly turning the engine. The second attempt normally works. This may be a starter drive/Bendix or solenoid problem.

Current suspects

Because the genuine camshaft sensor did not fix P0341, I am now considering:

- Poor connection in the camshaft sensor plug
- Damaged camshaft signal wiring between the sensor and PCM
- Damaged or incorrectly positioned camshaft trigger wheel
- Incorrect mechanical cam/crank timing
- Unstable crankshaft signal
- PCM input fault
- Incorrect PCM software or remap calibration

The next useful test is probably an oscilloscope test of the camshaft and crankshaft signals at the same time, comparing a cold successful start with a hot failed restart.

Has anyone experienced the same P0341 and hot restart problem on a 2.0 EcoBlue SID211?

Any known problems with the camshaft trigger wheel, wiring, mechanical timing or PCM would be helpful.

[metalworker0]

Wetbelt.. not mentioned .. replaced or not .. if not, maybe early signs of failing, i don't know enough about the early signs!

Most the problems i read here though, linked with not starting, seem to be fuel related .. air leaks in fuel filter, tank pump failing, pump module(this is a relay on top of tank)

Hot start can be a problem with starter motor being near the end of life and supping all the power, or turning over too slowly . you have DMF .. when these start failing .. lots of swarf clings to flywheel .. and ends up in the starter .. and also disrupts the crank sensor
Auto stop start requires batteries to be at over 80 percent to work .. otherwise it's disabled.. i don't know how it goes about disabling .. but try to turn it off .. see if it makes any difference.
Using stop start will wear the starter motor out prematurely. and eat batteries and alternator sooner.

These are just other things different to what you mentioned .. you are going about it the right way and above is about all i can add as extra things to look at. for now!

all the best.mark

[WhoThatCar]

Thanks Mark, yet again
I appreciate the suggestions, with this forever problem maker of a vehicle.

Engine code is YMF6.

The Auto Start/Stop function is already disabled. The “Manual Restart Required” message only appears after the engine has fired and then died, so I believe the message is a consequence of the failed restart rather than the cause.

Rail pressure remains above 250 bar during the failed hot starts, and the engine does fire and briefly reaches around 1,000 rpm before dying. Once it stays running, it drives normally without cutting out.

The starter motor may still have a separate problem, as it occasionally seems to spin without properly turning the engine on the first cold-start attempt. I am investigating the starter and the main ground connections as well.
I've been on the same thought that the starter surges all the grounds and power, making it so that the camsensor is getting disrupted and distorted signals/timing.

Regarding the wet belt, the previous owner claimed it had been replaced, but there is no invoice, service record or other proof. Therefore, I have to treat the belt replacement as unconfirmed. With the persistent P0341 code, I agree that the belt condition, mechanical timing and camshaft trigger wheel should now be checked properly.

Thanks again for the additional ideas.

[metalworker0]

Just another thing

when i put a question to AI mentioning 2 litre ecoblue and sensors and the code .. it said it had two camshaft sensors, one for each camshaft in the reply hmm

i then asked if the transit 2.0 ecoblue had two camshaft sensors .,. it said it only had one .
so now i do not know if the first answer was true.

if it does have two, then that's one you missed.

all the best.mark