I have a 96 Chevy Beretta with a 3.1 6, with about 74,000 miles. The fuel milage has been rather low running around 14 miles per gallon. This is mostly city driving with short trips less than 5 miles each trip. Is there anything I can do to improve the gas milage? The car starts and runs well. The car will get about 28 if you take it on a highway trip. Please reply to the group or to (socrates at locutus dot org). Marty
That seems way too low for in town driving, even for a 3.1. Manual or automatic transmission? If auto, is it shifting correctly? What was the original in town and highway rating for that car?
"The car runs well" but there must be some explanation for that much fuel loss. Failure in mixture control or ignition timing? Bad cylinder but you just didn't notice because it's a big engine? Leak in gas line or gas tank? Any unexplained gasoline odors lately? Theft?
Conservation of mass applies. That gas is going somewhere, either out the tail pipe, onto the ground, or into somebody's siphon hose.
If it's the engine, then a good diagnostic is probably in order. Timing, compression, emissions check, diag codes, etc. I'm just throwing ideas here, sorry I can't be of more specific help.
--Dave
Don't know where you live, but has the weather been very cold there lately?
Do you use the handbrake in the winter? Do not use handbrake in winter if you live in a climate where the roads get snow covered.
Someone has already asked about whether it is stick or auto. You can do a lot with a stick to improve mileage.
That is low even for burned out O2 sensors. As another poster said, leak, siphon, or out the tailpipe, More than likely the catcon is burned out, too. Check all intake gaskets and hoses for vac / air leaks. Check fuel pressure, regulator, and maf. Check O2 sensors.
Thanks for the replies so far. I have a couple of questions. The car has 2 oxygen sensors. Which one should I replace? And, I am not getting any "check engine light". Shouldn't the light be on if the sensors are defective? More on the car, it has an auto trans and I am sure there are no fuel leaks because I had the fuel line replaced back in Oct. I have owned 2 of these cars in the past and the gas mileage was always poor during the Winter around 14 when it is below 20, but in the Summer it should get around 19. I only drive about 200 miles per month, so an inexpensive repair would be best. With the price of gas hovering around $3.19 in our area, it would be nice to get better gas mileage. Also, I don't know if it is running rich because there are no emission tests in our area. Marty
Before you go swapping parts there is a simple test you can try. Start your car and get it fully warmed up. Go to a gas station and fill the tank. Go drive the car for 30-40 miles, on the highway if possible. Return to the gas station and top off the tank. Next, divide miles travelled by gallons used to get your actual mileage. Find out what your actual mileage is before you try to fix a problem you may not have.
I believe your mileage is low because of the short trips of less than 5 miles in cold weather. If you also let the car idle to warm it up that will reduce your mileage even more.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.