# Significant loss of gas mileage on a 1999 Altima

**URL:** <https://community.cartalk.com/t/significant-loss-of-gas-mileage-on-a-1999-altima/10554>\
**Category:** Maintenance/Repairs\
**Created:** [February 12, 2008, 2:16am UTC](https://community.cartalk.com/t/significant-loss-of-gas-mileage-on-a-1999-altima/10554 "2008-02-12T02:16:11Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![jbleskacek](https://avatars.discourse-cdn.com/v4/letter/j/54ee81/32.png) [@jbleskacek](https://community.cartalk.com/u/jbleskacek)\
**Post date:** [February 12, 2008, 2:16am UTC](https://community.cartalk.com/t/significant-loss-of-gas-mileage-on-a-1999-altima/10554/1 "2008-02-12T02:16:11Z")

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Very recently, I have noticed a significant loss of gas mileage on my 1999 Altima, I used to get 26-29 MPG until 3 weeks ago. All of a sudden I am now at 17. No engine lights have come on, and the car seems to be running fine, maybe a little more sluggish. I have replaced rotor, cap, plug wires, transmission fluid, fuel filter, switched gas stations, nothing has seemed to work. I thought it could be an O2 sensor or plugged catalytic converter, but again there have been no service lights displayed. Any suggestions? Thanks in advance. jb

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**Author:** ![pleasedodgevan](https://avatars.discourse-cdn.com/v4/letter/p/51bf81/32.png) [@pleasedodgevan](https://community.cartalk.com/u/pleasedodgevan)\
**Post date:** [February 12, 2008, 3:22am UTC](https://community.cartalk.com/t/significant-loss-of-gas-mileage-on-a-1999-altima/10554/2 "2008-02-12T03:22:33Z")

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Spark plugs? Bad wheel bearings, stuck brake caliper, bad calculator, city driving, stolen gas, fuel injector jammed. I don’t believe you got 26 to 29 MPG. The overall MPG rating on a new Altima is 23. Consumer Reports. You should get at least 17 MPG.