Hi,i have intermittent cutouts,check engine light on,the engine restarts after a lot of attempts with check engine on,scanned and always throws engine speed sensor g28 no signal,i clear the fault and engine starts.Some other times i have during cutout check engine light on,epc on,oil blinking and speedo to zero while engine is still running with reduce power.I have changed the g28 and g40 sensors but i have same problems,the ecu is marelli 4lv,can you help me?

Thank you

if you have changed to a known good sensor, then I'd suspect its connector or wires.

And if they are in a good state and with continuity to the ECU (need a wiring diagram, sorry for the right pin, I can only suggest earth connections. Battery negative to engine.

Connect a fat jump cable from battery negative to the block, and see if it still happens. Make sure the clip can't fall off and foul something.

Verify good clean earth to the block before you go any further.

After that you're into continuity testing of the wiring for which you will need an ECU pinout diagram. Have you carried out a full visual inspection of the engine bay wiring? You'll be looking for accident damage, aftermarket equipment installation damage, missing heat shields or clips allowing bits of the loom to waggle about and get damaged.