Hello,
I have Golf 6, 1.6, 102hp, CHGA engine code, with LPG, but it's the same like MPI/BSE engine, without EGR valve and MAF sensor.
My golf have spent around 300.000 km, and 20k by me, and still run great, without any issues while driving.
But I have the same problem as above, shaking on idle sometimes, but revs are stable.
Changed many things, all tested and changed by me.
What I have tried:
Changed brand new:
LPG injectors & LPG Map sensor about LPG pressure
Lambda (Oxygen) sensor (first one before catalytic conventor)
Spark plugs
Ignition module/coils
clutch pedal and used whole manual gearbox (5 gears).
all filters/oil has changed on time (both, Engine and LPG filters)
Belts/bearing on time
Maintenance/Cleaning/Check:
Compression test excellent (that means valves are ok, also great pointer is that the sparks are not oiled or burned/dark )
Vacuum valve - Cleaned & checked
All rubbers/pipes on air intake system - Cleaned & checked
Throttle body - Cleaned & calibrated
Map sensor - Cleaned & tested
Other diagnostic test like read realtime sensors & parts variables (I have many device including original VCDS)
After all stuff above, the problem is still remain. Talked with many people and read on every forum and conclusion is that the problem is very often and has not real solution. Many owner say that the engine simply works like that and forget it about changing parts and waste your money, in other ways, the positive thing about this engine is that the maintenance is fairly cheap and engine run well.
Because I have petrol and LPG, and the problem still exist on both fuels, I can exclude petrol Injectors and Fuel pump as possible parts to search for the problem. Also flywheel is not dual-mass, my opinion is not space to search for problem there, like many people does.
The only thing that partially works for me, it's up revs to 820-830 by VCDS tool ( that is the same as you turning on your AC because in that moment your revs raise) and idle going to be more stable and shaking become fairly calm, but idle fuel consumption raise up to 30% as well.
If someone have another experience and resolve this problem in other way, please share experience here.
Best Regards,
S. from North Macedonia.