I have a 94 Chevy Corsica it's getting about 19 mpg highway when it should be getting a lot better I replaced spark plugs fuel filter before I replace the O2 sensor wondering what the problem could be

Dan Dugan

Asked by Apr 04, 2014 at 12:25 PM about the 1994 Chevrolet Corsica 4 Dr STD Sedan

Question type: Maintenance & Repair

2 Answers


Don't know where you live but if you're trying to compare mileage that you were getting over the summer to the mileage this time of year, it will always be bad. Cars always get worse mileage during the winter months. They also change the gas to a "winter blend" which is worse for mileage than the summer blend. Try checking your mileage again when the weather gets warmer. You will see a difference. Check your air filter. That never helps running a dirty one.


That should be the 3.1 engine. If you have had better milage and it has dropped without codes it is a pain to find the cause on these cars. The best method to chase down the issue is to read the live data in the ECM to see which sensor is NFG. Since this is a '94 it is OBD1 and the scanner market is fading away. I use a ALDL cable and my laptop (about 70 bucks for the cable) to read the data. But for now I would get a cheep manual and check the other sensors. The ECT is always a good one, if you have a low temp reading the ECM will not enter closed loop and trim your fuel with the 02 sensor? You can also check the EGR valve? If it's flooding or rich check your fuel pressure regulator and injectors?

Your Answer

Add photo

Related Questions

  • Chevy Corsica V6: DTC-64 Manifold Sensor Circuit Signal Low 3 answers

    Hi Everyone! I'm a newbie to this forum as well to Corsica's. I recently picked up a 1988 Corsica for a commuter that im trying to get to pass smog. Im having trouble with a DTC code 64. My programmer...

    1988 Chevrolet Corsica


    Maintenance & Repair

  • engine bogs down at highway speed 3 answers

    i have a 96 corsica 3100 v6 change the plugs, wires, one fuel injector check engine light does come n when she bogs down cant figure whats wrong should i change the fuel pressure regulater or the o2...

    1996 Chevrolet Corsica 4 Dr STD Sedan


    Maintenance & Repair

  • 1995 Corsica 3.1 problem accelerated from a stop 2 answers

    My Corsica has a bad hesitation from a dead stop. I press on the accelerator and it almost stalls then it takes off and runs fine through the gears. This happens from every stop unless I ease into t...

    1995 Chevrolet Corsica 4 Dr STD Sedan


    Maintenance & Repair

  • chevy corsica starts but then dies 2 answers

    1993 Chevy Corsica 3.1 starts, then dies. give it gas and then all it does is sputter and back fires out the air breather. wont run . don't know what to do

    1993 Chevrolet Corsica


    Maintenance & Repair

  • 12 MPG very poor mileage 13 answers

    I am having a very poor gas mileage. On highway it goes to over 19 MPG, and in the city it drops to 12 MPG. Air filter, tires pressure and spark plugs are ok. I need to check the fuel filter, but the ...

    2006 Chrysler Town & Country LX


    Maintenance & Repair

Search Chevrolet Corsica Questions

Chevrolet Corsica Experts

#1 littlehorn
Reputation 230
#2 Rabidd
Reputation 110
#3 tenspeed
Reputation 90
View All

Related Models For Sale

Used Volkswagen Jetta"
625 Great Deals out of 32,204 listings starting at $1,200
Used Chevrolet Impala"
948 Great Deals out of 35,753 listings starting at $700