Gas Mileage

[Tino22121]

I have a '01 Impala with the 3.8 and about 105k miles. I consistantly get around 29-30 Highway, and 25-30 City. I don't do much city driving, all highway to and from work. I'm actually suprised to see the low numbers. Even running the a/c I get 27 hwy. I certianly hope my gas milage stays where it's at.

[57chevyragtop]

That's real good for the 3.8 ltr. I was pretty disappointed in my 3400's 14-16 mpg during the winter but thought maybe had to do with short town trips every couple of days. Found I was right when I finally got a couple of long highway trips in at 34 mpg. I would still be happy if it were 29-30 for this size vehicle when you figure a new Saab 9-3 is rated at 17-30 with a 210 hp. 2.0 turbo four.

[blmitch11]

Originally Posted by CT Tim

Yea, I have a 2000 w/ 100k on it- I was wondering if either of those factors played a role considering you would think a lighter car like this would be getting better mileage-I know someone with an early 90's lincoln town car that gets an average of 18 on highway and that things gotta have about at least half a ton and another 6 ft. on the impala. -Oh well

I also have a 2000 with 100k on it...I was told my EGR Valve was bad and that's why i had such poor gas mileage..maybe something to check into

[Mikey-Mike 02]

Hi, My 3.4 had trouble starting w/a warm engine so I put some Bosch Platinum+4 plugs in there and some MSD Ignition wires... The car starts really good now and my gas milage went up noticeably.

A guy from work put those plugs in his sisters Blazer and she reports a 5-7 mpg improvement!!!!!

[gw84]

'99 Lumina LTZ (3.8L) (65K) I've averaged between 21 and 23 doing mostly city with some highway driving. It sure seems like the first quarter of the tank goes by slower than the last 3/4. I get around 100 miles on the first quarter then only around 200 on the last 3/4. CrAzInEsS!

[anuta1186]

Save on gas and help your car run smoother. Check it out. (link removed by staff)

[twospirits]

Don't know why you are advertising a product for saving gas when we do not allow advertising/spam.

Besides where you are going they don't use gas.
Welcome to Banlandia.

Have a nice trip

TS

[57chevyragtop]

Originally Posted by gw84

'99 Lumina LTZ (3.8L) (65K) I've averaged between 21 and 23 doing mostly city with some highway driving. It sure seems like the first quarter of the tank goes by slower than the last 3/4. I get around 100 miles on the first quarter then only around 200 on the last 3/4. CrAzInEsS!

You didn't know? The gas tank is divided into 2 parts, The top 1/4 is used for highway and the bottom 3/4's is used for city.... This is not an uncommon thinking on your part as it does seem to be that you get better mileage on the first 1/4 used. However the float on the gauge does not register the fuel above the bottom of the float which can be as much as three gallons in some vehicles. So when your gauge starts to register the drop, you have used that portion not measured which includes that which is in the fill tube as well. This can very with fill up, that is why when measuring mileage it is best to use the same pump and same number of fill clicks for accuracy.

[SpinnerCee]

I'd say it matters how we are determining mileage.

I've never trusted the Impala (LS) computer display, but it tends to average out around 16-21 in short trip city driving.

Therre are some things that seem to have an impact on this generalization:

Using the AC can cut about 10mpg off that average and make a differerence in the car's throttle response -- the AC compressor really loads the engine especially at low RPM where it spends most of it's time.

I also think the 3.8L has a powerband that starts pretty high (>2500 RPM), but the PCM logic short-shifts the tranny really early (ie: before the engine is making any "useful" torque) to save fuel and keep the RPMs down to save the engine.

Using the overdrive (D on the shifter) helps highway mileage a lot more than city driving -- We usually drive in (3) or (2) around the city because once the tranny shifts into overdrive at around 45mph the RPMs drop to almost idle and braking becomes more difficult (the engine kind of "runs up" on the brakes) and the constant gear hunting becomes a bit annoying. Also, once the tranny is in OD on the highway, you DO have to floor it to make it downshift to get that "passing power" -- and it's very harsh -- try driving in (3).

I think the 2001 Impala is just too heavy for the tune on that V6.

[sl1cksNsk1n1es]

Originally Posted by CT Tim

Is the 175k on the original engine? I'm also guessing that the tranny had to be rebuilt,just out of curiosity how long did the original one last you? The one that I purchased went to about 90k but it also started out as a lease vehicle in Jersey so I imagine that took a toll.

Tim

I hear a lot of people talk about these engines poorly. i deliver food for a part time job..... 90% city. i always mess with the milage stuff, the better milage the more money i make. mine is a 2000 3800 series II. city driving i manage around 18-19 but i also drive from carbondale ill to north chicago about 5-6 times a year and it is between 420-440 miles and i have made it in one tank. i always try to get higher and higher gas milage every time. i mean i take the trip more than once a month on avereage. my best is 28.1 miles per gallon going 76 Mph no stops. burned a strait tank of gas at 76mph on cruse control. i have had the car since new and it has 140,000 and i have never had any major problems. some electrical things and it needs a quart of oil between oil changes.

[adamace1]

Hello Everyone. First post for me anyways I have 04 with the 3.8 I get 22-24 city and 30+highway, I don't use the trip computer cause it is off i use the old math method. Last trip i took i went 250 miles one way and i got 33mpg It was all 70mph driving with maybe four stops in the four hours it takes.

[usarmy]

I get about 18.3 mpg on my 03 impala 3.4 L,,, with 106 000 miles,,,

[3rdChevynow]

2001 9C3 3.8, 119,000 km now. 27000 km driven in 10 months, averaged mileage: 9.15 L/100 km (25.6 mile/g). Replacing the regular papaer air filter with a K&N one saves significantly (fuel usage drops from 9.27 L to 9.0 L per 100 km 26.1 mile/g now). 90% hiway driving but 1/4 hwy with traffic jam.

[adamace1]

Originally Posted by usarmy

I get about 18.3 mpg on my 03 impala 3.4 L,,, with 106 000 miles,,,

IS your parking brake on? J/k I wonder why?

[tanasdad95]

I have a 02 with the 3.8, and it has 120,000k on it. I drive a average of 300 miles a day and get 27MPG. The diffrence between the computer and checking it at the pump is about 1 MPG. My wife and I enjoy the car, We also have a Expedition and a Sable. The Impala is buy far the the most economical and sporty.