Hello Folks,
I have a 2011 Lexus GS 350 AWD, in exellent condition, it has 106K so far, I take good care of this beauty, however, I noticed lately (since September of 2019) that my fuel consumption has gone way too high, from 11 liter per 100KM to 18.2L per 100KM. my driving habits haven't change, I still use high octane fuel (super). what is happening? do I need to change spark plugs, air filter or this is something more for the dealership?
any advice?

thank you

 

If you havent replaced the plugs then I would go ahead and replace them with factory oem, and not fakes that are sold on ebay. I would also change the air filter, clean the throttle body inside and out by unbolting it, check the tire pressure, but more likely the cause of your mpg loss is from the gas. In cold climates the gasoline companies use a winter blend to help with the colder climate. This winter blend is not as efficient as regular blend.

 

Thank you ibidu1 for your reply.

I will be doing this. What brand name for spark plugs do you recommend?

 

OEM plug, the denso iridium is the same. But like I mentioned there a ton of fakes, so buy from a reputable source. Rockauto has them for $12 a plug heres a part number FK20HBR11

 

thank you so much!!

 

If the spark plug change doesn’t do it, you might want to try a Valve System Service; it worked for me.

 

Whats a VVS? Cleaning the induction chamber/top engine clean? If so that is a good idea aswell, even running seafoam through the intake manifold vacuum hose is also good.