Re: Hard time getting more MPG - 98' Sunfire
 

I'd stay away from pumping up your winter tires. you want as much traction as you can get. that is an easy tradeoff for me especially during winter months and in extreme conditions.

I am going to make some assumptions here as your car is very similar but not the exact same car that I have. you don't want to cover the section between the bumper and the radiator underneath. my car gets 99% of the cooling from there....literally. the front grill basically does nothing. my car has a little lip under it that catches the air and directs it at the radiator. I have been told that if this lip gets damaged or falls off, I would start to overheat.

the big thing with the grill block is to put it on in such a way that it can be easilyremoved until you know it isn't too much. I used zip ties at first and carried a pair of dikes (diagonal cutters) with me just incase. mine was fine with a full grill block. I ran for about 2 years before permanently covering it with fiberglass and bondo.

(shameless plug)
please ignore cheesy music
https://www.youtube.com/watch?v=4n6iNOxl5PA

big thing is to get a gauge. you don't know what works until then.

I would assume that your engine is pretty lose by now. I wouldn't go to a lighter oil but I honestly haven't tried it myself. it might be worth looking into.

realize that my mileage is more because I drive a lot and a lot at a time. when I don't have my daughter, it is 35 minutes at a time. when I do, it is more like an hour and change almost constantly running. that helps a lot. short runs kill mileage. the guy that drives 5ish miles to work is always going to see rough MPG but he doesn't burn a lot since he is only 5ish miles away.

if you do want to talk more about it. just let me know. I have tried quite a few things on the old cav. she has been a good little car. I might try to keep her an even decade.

Re: Hard time getting more MPG - 98' Sunfire
 

Beef,

Yep, the Cavaliers and Sunfires are basically the same car. I've included a pic of a front clip from a 1998 sunfire just like mine (though it's not mine). The two black vents are useless and are blocked off behind the little honeycomb grilles. I'm thinking about filling these and smoothing the bumper out like you did to your car.

https://t2.gstatic.com/images?q=tbn:A...qlaBkmKnc7rDp5

Tonight I went out and bought some adhesive weather strip and filled the gaps around my headlights. When I was out I also picked up a can of seafoam and dumped it into the tank.

While I was at the store I noticed "wiper wings" they are little plastic wings that fasten to the wiper arm to "give a better down stroke of the wiper", but I was thinking that they would be good for the aerodynamics point of view. When you look at the hood of our cars you can see that the first thing on-coming air hits is those wipers and wiper arms.

Re: Hard time getting more MPG - 98' Sunfire
 

I used plexiglass the first time and covered mine with it. you could definitely do something with the front end of that car. it is like you have two little parachutes on the front end of the car.

around here we have a place called pull-a-part. my front bumper was ~$25 and I bought a spare one to work on and got it just so and then swapped it out. that way I didn't have to ride around without a bumper for a while. btw, pull-a-part is a junk yard.

I'd have to look up wiper wings. not sure what they are.

Re: Hard time getting more MPG - 98' Sunfire
 

There must be something mechanical that is wrong. I don't think grille block will give you that much but time will tell.

I would hope you could get at least 35 mpg highway.

Have you pulled codes with a OBDII reader? Checked vacuum leaks?

Re: Hard time getting more MPG - 98' Sunfire
 

there could actually be nothing wrong. if we could recap just to verify...

he's driving:
in bitter cold
with snow tires
a large 4 cyl engine
an auto transmission
also, he's replaced needed filters and sensors, not to mention the car has a lot of miles.

now, the OP doesnt specify the length of trips or want type of miles. if the miles are mostly short trips and/or city driving...well, i'd say there certainly is likely nothing wrong w/ the car or his calculations.

warmer weather, street tires, and improving driver techniques should be quite revealing as time passes. best of luck to you. keep us posted and continue to learning...

Re: Hard time getting more MPG - 98' Sunfire
 

Thanks for the reply.

Most of my driving is "in town driving" during the week, but highway trips on the weekends. I would estimate that I put on roughly 30kms a day just going back and fourth to work and running errands in the evening. Work is about 10-15kms away.

The car is mechanically sound except for a bad belt tensioner that is "ticking" at the moment.

The snow tires that I have are actually studded as well.

Re: Hard time getting more MPG - 98' Sunfire
 

Hi there,

I have an OBDII reader and it shows no faults. Vacuum lines are all in good shape and connected proper. About every three months I take the intake tube off and spray out the throttle body and vac lines with TB cleaner.

Re: Hard time getting more MPG - 98' Sunfire
 

Sounds like you just need to move down to Texas. :)

Re: Hard time getting more MPG - 98' Sunfire
 

Hey guys,

Just an update on my progress. Just from a few mods that i've done in the past few weeks, i've been able to get 315kms out of a little more than a 1/4 of a tank of fuel. I'm happy with these results. Especially for this time of year!

I've purchased a "Turbogauge IV" from ebay. It looks very similar to a scangauge, and offers the same options. I can even plug it into my PC and display a chart with my readings. $90. With the savings from this tool it should pay for itself though.

Here is a youtube vid about it:

https://www.youtube.com/watch?v=9-xKqqxuquc

Re: Hard time getting more MPG - 98' Sunfire
 

Very interesting.
https://www.amazon.com/SainSpeed-Turb.../dp/B005IV0MXQ

https://ecx.images-amazon.com/images/...EL._SS400_.jpg

That really DOES look a lot like the SGII but the SGII can't plug into the PC and has fewer buttons. This deserves its own thread.