The engine's smooth running system balances the rpm variations for each individual cylinder caused by varying injection volume and cylinder efficiency. This is obtained by an application that sends an exact fuel volume to an individual cylinder for every injection.
The limit values depend on injection volume and are between +/-4.9 and +/-5.9 mg/stroke.
The function is active within specific limit values:
Engine speed range: idle up to 3500 rpm.
Engine speed-dependent injection volume: idle up to 2000 rpm, injection volume should be <60 mg/stroke. Between 2000 rpm and 2500 rpm, injection volume should be 60 mg/stroke to 45 mg/stroke. Over 2500 rpm, injection volume should be <45 mg/stroke.
Monitoring:
If compensation for any cylinder ends up outside limit values, the following malfunctions may occur:
Smooth running adjustment, correction volume too high or too low: The value for at least one cylinder has been below or above the limit value.
Engine running control for cylinder X, correction volume is too high or low: The value for cylinder X has been below or above the limit value while correction volumes for the other cylinders are OK.
The max. compensation depends on the injection volume and is between +/-3 and +/-6 mg/stroke.
The indicated amounts must be between the following limits for all cylinders:
Min.: -5.0 mg/stroke.
Max.: 4.0 mg/stroke.
Evaluation results:
Ok, -5.0 to 4.0 mg/stroke.
Critical volume, <-5.0 or >4.0 mg/stroke.
An unacceptable deviation in correction injection volume may have the following causes:
A defective injector.
Low compression.
Defective exhaust gas recirculation.
Test conditions:
Engine idling.
Procedure:
Start the function.
Follow the instructions in the program.
The function is done.