2jzdc

Hey everyone,
I'm coming from a non vvti SC400, to a 98 GS400, what I noticed was that the GS400's mpg was worse than my prior non vvti sc400.
I drive like a grandma and was able to get 330 miles a gallon on the SC4, versus only 280 on the GS4. So I checked the rated MPG, and noticed it was rated 17CTY/23HWY, also did a search on the 98 LS4 and SC4, and noticed they were rated better.
Why???

BiGEZ

iTrader: (24)

When last was the car tuned up? Might be time for some new plugs, O2 sensors and such.

2jzdc

Just bought the car so did tons of maintenance. Oil change, new spark plugs. Replaced PS pump & hoses, brake fluid flush, new KN air filter. Car has no check engine light so I would assume with all the maintenance I've put into it, it would be performing as such.

Letsride

Whats the mileage?

LexusK

iTrader: (14)

I go about 250-260 miles before the light comes on and fill up right away. Is this not normal?

2jzdc

180K

Yeah I get similar mileage to this. But I still don't understand why the LS4 and SC4 gets better gas mileage with the same VVTI 1UZ.

Letsride

From my experience with the 1u's is that over 120K these cars need to have the fuel system cleaned. I run a couple of cans of seafoam through it, change the O2's, and most importantly....reset the computer. Give that a try and then report back...