I am getting really bad gas milage on my car for a while now. approximately 14mpg city. Dont know why though. I just changed the oil w/ full synthetic oil, changed spark plugs recently, and I added a K&N filter. Havent changed the O2 sensor yet but there is NO check engine light on. What could be the problem?

 

14 MPG is pretty low for an ES... mind as well drive an SUV. Check your tire pressures and make sure they're at the recommended level (~32 psi). Also check the tread of your tires while you're at it. Do you use the A/C often? If so, think about turning it off while driving and rolling down your windows; A/C is another factor which affects your mileage. Do you use regular fuel? If so, consider the change to premium (93 rating); I've started using premium recently after many years of using regular, and I see mileage increase by 2 MPG between the two brands.

 

quick question: what year ES, how many miles?

edit: duh, just saw profile. 93 ES with 160K miles.
hmmmm. depending on the type of driving your ES has seen, you *might* want to consider using traditional non-synthetic oil now that your car is getting up there in miles. maybe go half-synthetic for a while, then switch to fully traditional oil.

 

I dont use the A/C cause its already cold here in Philly. Tire pressure is good. I get worse milage on regular oil. It has helped a bit since I changed to fullsynthetic. I was just wondering if there is anything mechanically wrong with it.

 

Whats your driving style?

 

Some people have reported decreases in gas mileage from using K&N and other types of aftermarket cone filters. You could try going back to stock to see if this improves things. Some of the filters can deliver too much air and confuse the mass airflow sensor.
If you're spending an hour a day in stop and go traffic with constant idling and accelerating, that will drop your mileage, compared to driving at 40MPH for a mile at a time, etc. Do you have a stop and go daily commute?
Does your highway mileage appear normal?

 

In my old Bonneville, I would see the gas mileage decrease 2 to 3 mpg when the PCV valve was getting dirty. I'm not sure about the lex engine, but if its got one, you might want to check it. It is not that expensive to replace.

sj

 

you wanna know what...and im not bragging...i think my es gets the most awesome gas mileage ever.....i have driven anywhere from 400-450 miles on one tank of gas....and thats the truth..its mostly high way driving....but some city....the light is on by the time it gets past 400....but i can always get that much...i figured that s gotta be at least 27 or 28 mpg

 

anyone know where the pcv valve is located? any pictures would be great. thanks

 

I've been worried about mine as well. I average 20-21 mpg overall. I'm easy on the pedal, and my commute is a fair mix of city/hwy. Am I within normal range? I do have 120k on the clock, FYI. Feedback is appreciated. Thanks!

 

the pcv valve is a little thing located next to the manifold. I will go look at my car later today and try to tell you exactly which one it is, but it is an easy thing to replace.

 

According to www.Lexus.com there is a PCV valve on the 1MZ-FE engine and it should be replace at 60k or 90k depending on the inspection at that time. The person who replied to the inquiry failed to pinpoint the exact location.
I haven't looked yet. They are usually easily accessable.

 

where is it ??? My gas mileage is a bit lower also .

 

anyone have any idea where the PCV Is? Ive looked everywhere...

 

I found the PCV valve. In my attempt to remove it, I broke the piece that holds the PCV valve to the engine because it was so brittle. The valve is the original valve and has never been changed. It looked terrible. The car is now at the Lexus dealer to have that fixed. Kinda suck trying to change a $3 part ending up to cost much more than that.