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I have a 2009 GS 350 with right under 39K miles and it is getting about 11 MPG. Have put in a new air filter, new oil and oil filter and fuel injector cleaners in the gas tank and still around 11 MPG!! Anyone have any ideas what could be wrong? Any help would be greatly appreciated. Thanks
You can try spark plugs, but make sure to use oem or original denso part number FK20HBR11 they are a bit pricey but these are what work on our cars. Becareful of knockoffs on ebay, make sure to buy from a reputable source.
I would check the air tire pressure, I would run 35 or 36 psi all around. If you can afford to run premium fuel I would run it as that helps with the mpg. Also drive with a light foot, dont go hot rodding at every green light.
Clean the throttle body, simply remove the intake boot on the throttle body, all it takes is a phillips screw driver. grab some wd40 and a rag and spray and clean it. With your finger carefully push open the butteryfly flap inside and clean throughly from the inside.
Where are you located? How much time is actually spent driving vs idling? How many miles total did you drive?
These are all factors that play into MPG. I have a 4 banger that got 12 MPG when my commune was <2 miles and spent about half the commute time idling at lights. This was in Queens, NYC.
When my commute changed to mostly highway at 25+MPH, it got a lot better, around 20 MPG.
I gave this car to my brother and he lives in Palm Springs and is retired so not any idling time in traffic. He needed to go to LA for the w/e so not much time to do much before leaving. The MPG reading is from the car's computer and instrument cluster. He did put 36 PSI in the tires though before leaving. It was reading about 11 MPG before he left but on the freeway it got up to 25.5 MPG which really isn't bad. He did notice a lot rougher ride with that tire pressure but that's to be expected not to mention that LA roads aren't exactly the best in the nation!! lol I'll get him to do a new PCV valve and clean the MAF sensor when he gets back home and eventually put in new spark plugs down the road. Thanks to everyone for the suggestions. :-)
I gave this car to my brother and he lives in Palm Springs and is retired so not any idling time in traffic. He needed to go to LA for the w/e so not much time to do much before leaving. The MPG reading is from the car's computer and instrument cluster. He did put 36 PSI in the tires though before leaving. It was reading about 11 MPG before he left but on the freeway it got up to 25.5 MPG which really isn't bad. He did notice a lot rougher ride with that tire pressure but that's to be expected not to mention that LA roads aren't exactly the best in the nation!! lol I'll get him to do a new PCV valve and clean the MAF sensor when he gets back home and eventually put in new spark plugs down the road. Thanks to everyone for the suggestions. :-)
how long before you took the 11mpg reading had the mpg history been reset? If it hadn't been too long, it can definitely skew the results until after some miles are put on it.
I gave this car to my brother and he lives in Palm Springs and is retired so not any idling time in traffic. He needed to go to LA for the w/e so not much time to do much before leaving. The MPG reading is from the car's computer and instrument cluster. He did put 36 PSI in the tires though before leaving. It was reading about 11 MPG before he left but on the freeway it got up to 25.5 MPG which really isn't bad. He did notice a lot rougher ride with that tire pressure but that's to be expected not to mention that LA roads aren't exactly the best in the nation!! lol I'll get him to do a new PCV valve and clean the MAF sensor when he gets back home and eventually put in new spark plugs down the road. Thanks to everyone for the suggestions. :-)
If the car is getting 25.5mpg average on the screen then thats great I wouldnt do nothing to it but change the oil/filter/ air intake filter. I would leave the spark plugs, there pricey and will last until atleast 80k miles.
When I had the car I swear that I could set the instrument cluster to MPG and hit a reset button somewhere and it would reset the MPG immediately (either sitting still or driving down the highway). For some reason that doesn't work now or my brother is doing something wrong when he tries to reset it. The 25.5 MPG was on the highway going to LA. Once he got there and drove in town for awhile the MPG went down to 12.8.
I think it only resets when you open the gas door. 12.8 is bad, but like I said it depends on the driving style. Is that a lot of stop n go/idling city driving? Do you guys drive the car fast?
I think it only resets when you open the gas door. 12.8 is bad, but like I said it depends on the driving style. Is that a lot of stop n go/idling city driving? Do you guys drive the car fast?
I don’t think it only resets when you open the fuel door as I have tried that. I think it’s when the sensor reads a higher than before reading in your gas tank. My 0.02$
Lousy gas mileage
