Is 16 mpg normal for a 4 cylinder 1997 Buick Skylark?

Question

I have a 1997 Buick Skylark Custom 4 door. It has 70,000 miles on it. I just bought it a couple weeks ago, and have tested this mileage on two full tanks of gas now. It only gets about 16mpg in the city. This just doesn't seem right for a 4 cylinder engine. My piece of crap 1994 Dodge Caravan gets 19 mpg in the city and that's a minivan with a horrible running 6 cylinder. So anyway, I talked to a mechanic briefly and he said that if something was wrong with it that the check engine light should be on. He also said it would cost $80 just to give it a diagnostic check or whatever. Any suggestions on what might be wrong with it or what I should do? Thanks!

Answer 1

it should be more than 20. Take it to Pep Boys, AutoZone, O'Reilly's or some other local auto parts store and they'll put a diagnostic on it for free.

It might need a good tune up (new plugs) but way more than 16mpg

Answer 2

Change the fuel filter and PCV valve, make sure the spark plugs are in good shape and gapped to spec (as shown on the Emission Label under the hood), and try the other things other people are posting.

I recently changed my fuel filer, pcv valve and breather (my car is OLD I don't know if newer ones have a breather like mine), new spark plugs properly gapped, tightened up all the screws holding my carburetor together and to the manifold (you don't have a carb, like I said my car is old), etc. and have noticed a marked increase in fuel economy.

The only other thing I could think of is your coil may be weak, but if it is it probably would cause driveability issues.

Also try Motorvac service, cleans the injectors. A cheaper alternative is adding Chevron Techron to a tank of fuel. Works good, I used to use a bottle every year when I had my (fuel injected) Crown Vic.


I highly doubt the previous poster gets 21MPG city with the Dodge van with the 318 (5.2 liter) V8. Highway, yes but not city. Then again to me city means where I'm from, NYC, where 8 MPG is average for a V8.

Answer 3

Maybe it needs a good tune up. Btw I get at least 21-26 mpg on my 94 caravan w/a 3.3 in the city. I also used to get 21mpg with a brick of a van , a 92 b3500 dodge fully loaded with a 318. Try a little Lucas fuel treatment . Don`t overdo it. Just a couple ounces every oil change. To much is not good

Answer 4

Change the oil and air filter on it first, after that you need to get it tuned up, replace spark plugs, wires na dif it has a cap and rotor still replace those as well. make sure all the tires are the same size and have the correct amount of air in them as well. Little things like that can drasticly increase or decrease gas mileage. hope this helps

Answer 5

stop and go traffic of most cities same any 4 cylinder my truck an S-10 get about 18 city and 25 hwy.
other additives like an octane booster may help or an injector cleaner? but i don't trust either may be upgrade your gas ever once in while if mileage goes up that could be your problem not enough octane in gas your use in...cost wise your not gonna save unless you can "bus it' one day out of 5 that's what i did ....saved $30.00 over a month.

Answer 6

Hold it everybody!!!
Analyzing a vehicle based on in-city MPG is a fallacious approach! I can take my car and drive it in town and get as low a mileage as I wish to get right down to 0 mpg.
Bud, fill your tank, get on the interstate and drive it 30 miles with the cruise on or at a steady speed. Refill the tank. Refigure your mileage. After you do that, come back and ask us again with accurate info.

Answer 7

you can do a tune up on it for almost what he,s going to charge for the diagnoses on it,usually when a 4 cylinder drops in mileage there's something wrong,that one should get a little bit better than that on gas,if you don't have no check engine light the 80 bucks could be spent towards a tune up,sometimes a diagnoses is necessary though,but i,ll leave that part up to you,if it was me doing it id do a real good tune up,and see if that helps it,parts aren't going to be that much for that one,good luck on it.

Answer 8

do a tune up it should be getting alot better than that. plugs /plug wires/ air filter/ oil change /rotor button /rotor capalso burn some good gas it in once in a while.