Iveco 75e 160 tector low rpm acceleration problem

I am sitting waiting for spares from OK trucks workshop in Oradea, Romania. This is my 3rd week not joking.

The problem has been, when the truck is suppose to accelerate from 1000rpm to 1900rpm it take ages. When the rpm reaches 2000rpm and higher it takes off. Very similar to old 2 stroke.

I have cleaned all fuel lines. Changed filters. Cleaned fuel tank.
Changed one leaking fuel line.
Checked air intake for birds or mouse nest
Changed EBC sensor on rear brakes
Changed the sensor cable on the brake pedal
Checked the turbo charger impellers
Checked the exhaust brake
Had the Iveco computer analysis for faultimate codes none.
Checked fuel flow rate injector return 25ml per min.
Still no sign of the problem going away.
I have ordered a bosch fuel regulator for which I am waiting now 2 weeks.

Does anybody have some reasonable ideas?

75jez:
I am sitting waiting for spares from OK trucks workshop in Oradea, Romania. This is my 3rd week not joking.

The problem has been, when the truck is suppose to accelerate from 1000rpm to 1900rpm it take ages. When the rpm reaches 2000rpm and higher it takes off. Very similar to old 2 stroke.

I have cleaned all fuel lines. Changed filters. Cleaned fuel tank.
Changed one leaking fuel line.
Checked air intake for birds or mouse nest
Changed EBC sensor on rear brakes
Changed the sensor cable on the brake pedal
Checked the turbo charger impellers
Checked the exhaust brake
Had the Iveco computer analysis for faultimate codes none.
Checked fuel flow rate injector return 25ml per min.
Still no sign of the problem going away.

have ordered a bosch fuel regulator for which I am waiting now 2 weeks.

Does anybody have some reasonable ideas?

Does this have a Variable Geometry Turbo? if so it sounds as if the sliding vane shroud is stuck. (These are operated by a linkage on the outside of the turbo, moved by the ECU to match the effective turbine area to engine revs and throttle opening)
If seized up this could give your symptoms of no boost until 2000 rpm then lots of power.

If it doesn’t have a VG turbo, can’t offer any another suggestion.

The vehicle is fitted with Ganett waste gate turbo.

Are there any relays or electronic boards notorious for dry soldered joints? The roads are extremely bumpy and known for very large pot holes.

Yesterday was very cool moring. While the water temperature gauge was “zero” for the first 4 minute of driving everything felt okay as vehicle accelerated through the 5 gears before reverting to no pulling power between 1000 and 2000 rpm.

Could it be something like a coolant temp sensor?
Modern engines use all sorts of stuff to determine fuelling, so a dicky coolant or air temperature sensor could mean the ECU is not putting the correct amount of air/fuel through the engine.

The fuel regulator arrived after waiting 2 weeks. Fitted the part and tested the vehicle. Slow acceleration.

Checked all the fuel lines are connected as per manual. No fuel leaks. Test vehicle slow acceleration.

Removed the fuel pump and replaced with new pump. Tested vehicle, slow acceleration.

Just delivered the injectors to Bosch. These were calibrated last year. Waiting to hopefully get them back Monday after noon.

The injectors came back from Bosch. There is no problem with their operation. They are good.

What next EBC computer change out? (1800 + vat) Or wiring loom? (1100 + vat)

I personally think the computer analysis slow acceleration is very vague!!

The vehicle is still at the garage? What year are we in 2018 or 1918?

Today the truck was road tested with computer hooked up.

The speedo speed was 56km/h and the computer was reading 20km/h.
At lower speed of 20 km/h the computer was reading 5 km/h.

Is this faulty ecu or is the resistance of the wire high? Or is there sensor error?

High pressure fuel pump won’t show any fault codes seem to recall and it might still perform at higher revs although I’m not sure if it wouldn’t be a bit more misfirey than sluggish. Wouldn’t harm to check the fuel rail pressure.

Checked the fuel rail pressure is okay.

I delivered the both ECU’s to technical service that repairs these ECU unit in Derbyshire. Been told they cannot access the info to test the ECU. Are the ECU Units locked by the factory?