Injector. An atypical defect

From one side – nothing special, from the other – a defect, which appeared for the first time in my experience.



a) when the engine runs in Stratified charge, the power is as if reduced, you can hear ticking from the engine room when the required torque is increased (possibly – detonation in one of the cylinders);

b) when the engine runs in Homogeneous mode, with low RPM – normal performance, with higher RPM – feeling that some cylinder is losing its efficiency.


Parameters, which are correct:

a) mechanical efficiency of cylinders in idle (../F5/F7) – correct;

b) fuel mixture: Lambda and integrators in Homogeneous mode and Lambda in Stratified charge are correct – both in idle and driving;

c) both multiplicative type adaptations of injectors (../F5/Shift+F6/F1) and chemical tests of the injectors (../F5/Shift+F6/F3) are correct (well, for the chemical tests the difference of +/-5 .. 6% is observed in the 2-nd bank, but – all is as if in the allowed range).


Parameters, which are not correct:

a) increased opening time of the 6-th injector in Stratified charge, idle (../F5/Shift+F6/F1);

b) the adaptations of the 6-th injector in Stratified charge/idle (../F5/Shift+F6/F5)

As we see, MSD80 has increased the amount of fuel to inject in 6-th cylinder even for +45 .. 50% for the cylinder to reach correct mechanical efficiency.

Obviously, the injector injects the more or less correct amount of the fuel (because the Lambda and Integrators are correct in the Homogeneous mode), but doesn’t do this in a type of a fine mist. The injector pours the fuel, and the fuel very badly mixes with the air (bad atomization). In Homogeneous mode, by low RPM – in the situation, when there is a lot of time for fuel to mix with the ait – the cylinder works more or less correct. Stratified charge – in mode, when the fuel is ignited immediately after injection in the combustion chamber (and there is very little time to mix with fuel), the performance of the cylinder drops dramatically, because of the fuel burns badly.


The replacement of the injector radically solved the problem. Directly after starting the engine (even without re-adaptation), when it was switched to Stratified charge, the adaptations of the injectors came back to normal during 5 .. 10 seconds.