Nissan QQ 1.3 petrol, HR13DDT engine. Fuel rail pressure/HP pump regulator current during acceleration/deceleration. Double pulses regulator control at low speed/load.

When the air/fuel mixture enrichment goes beyond flammability point, combustion no longer takes place in cylinder which becomes an air pump. The whole amount of O2 which should have been used in fuel oxidation will pass by upstream A/F ratio sensor(together with fuel vapor) whose signal will show a ...

Scope the HP rail sensor and monitor the pressure drop for each injector as one or more may get sticky open and bleed the rail. Amp clamp on HP pump regulator and coil 1 sync signal. Post the all 3signals psdata file.

Cylinder nr3 after CAM signal has lower compression. Incomplete combustion=low power+smoke. Pick up inj nr1 signal with an amp clamp and synchronize it with RCT to find out the faulty cylinder.

Compression test and leak down test for each cylinder. Crankcase pressure at idle. Injectors back flow. Knock sensor signal under load. CKP signal under load(gear 4th from 1500 to 3500 rpm)

I think you have already got to the bottom of it. Could you share with us the fix?

Combustion takes place in cylinder.

Hi Tonnes 1977,
could you keep us update with this interesting case?
Thank you.

Any update?

Double check if the ECM part nr is the same with donor car one and swap it. Do the key prog in your car and it should start.