I put in a can of Royal Purple MaxClean Fuel system cleaner into my 2018 GLA 250, which was having some poor fuel economy. I also had previously changed out the battery.
I would say that the battery replacement made a more significant immediate impact on improving the fuel economy, but the Royal Purple fuel system cleaner really did help to smooth out the operation of the engine a lot, making it idle smoothly and more responsive.
Prior to the battery change and fuel system cleaner, the fuel consumption was ~ 9.5-10L/100km, now it's about 8.5L/100km , for 50% city and 50% freeway. Not bad for a CUV.
A forum community dedicated to Mercedes-Benz GLA owners and enthusiasts. Come join the discussion about performance, features, modifications, classifieds, troubleshooting, maintenance, and more for the 250 4MATIC and AMG 45 4MATIC GLA!