Hard time getting more MPG - 98' Sunfire
 

Hello everybody. I've been interested in the whole "eco thing" for some time, and have been squeezing every penny I can out of a tank of fuel for my 98 Pontiac Sunfire (2.2L Auto 4 spd).

I've been reading this forum for the past two weeks, and finally became a member the other day. The knowledge on this forum is amazing!

Living here in Eastern Canada we are right in the middle of a cold winter, and my gas mileage is sure letting me know!

The car has quite a few kms on it. 280,000 to be exact, but i've replaced just about every sensor, and filter on the thing since i've owned it (3 years). It's been a great car and runs well!

I've always believed in using synthetic products, and in turn my sunfire has had synthetic 5w30 in it for the three years. Current oil is Royal Purple.
What is everyone's view on Royal Purple? Previously I had been using Lucas 5w30.

In the past two weeks i've done a few things:
Cut a 3 inch hole in the air box and ran a 3 inch flex dryer hose to the exhaust manifold, removed my long antenna and replaced it with a smaller flexible rubber antenna. I have removed the licence plate that was mounted directly in the middle of my "v" shaped nose cone (figured this might have some wind resistance).

The tires on the car are winter studded at the moment and are at 32psi. The sidewall says "MAX 35 PSI". Should i inflate these more?

I've been doing a lot of coasting in Neutral when I can (ie coming to a stop sign, red light, or going down hill).

So far I haven't noticed much of a difference in fuel mileage. Six days ago I put 36 Liters of fuel in the car, and i've gone only about 280kms. So for roughly 3/4 of a tank i've only gone roughly 300kms.

EPA Average for this car is 23 city 25 hwy.

I'd like to get more out of it!

I've ordered a vacuum gauge to install on the dash, and i plan on doing a front end block-out with a front belly pan in the near future.

I know a scangauge would be a good option, but i'm a bit low on extra funds for one at the moment.


Any added tips would be appreciated!

Thanks!

Re: Hard time getting more MPG - 98' Sunfire
 

-winter tires are gonna suck (that's just what they do)

-winter gas yields less MPG and you may want to check and see if you are running E10 gas.

-there is an alternative to the scangauge 2. the ultragauge is around half the cost. google it, it's pretty neat.

-the sunfire is very similar to the cavalier (I think the same). my car is a '97 cavalier. if it works for one, it should for the other.

-grill block should do well for you (especially in canada)

good luck to you and your quest, I have had my car for close to 8 years now. I will say that my car doesn't go nuts but given the EPA estimate, I feel pretty good about it. mine is an auto trans as well. the scansauge was a huge help. I also have an ultragauge (in my other car). my conversion sucks but we may have close to the same mileage. I have 227k miles (not sure in kms)

****edit****

depending on how you feel about looks, I could give you some pointers on the grill block. I have been running with a WAI for a while on mine. my temps don't go that high and yea, it helps a little.

Re: Hard time getting more MPG - 98' Sunfire
 

I hear ya about the winter killing gas mileage, I was just starting to see some gains in fuel economy of my neon, until slme -15'C weather started coming around lol. I just put a warm air intake on mine, but I only check gas mileage on tank to tank averages so no way to tell if its helping yet.

Re: Hard time getting more MPG - 98' Sunfire
 

25 mpg highway is awful for a 4 cylinder.
How are you calculating your mpg?

Re: Hard time getting more MPG - 98' Sunfire
 

Very cold weather and driving in snow will destroy your gas mileage. Especially if he is doing what I do, and just using tank to tank fill ups to calculate mpg. Running your car for 10 or 15 minutes in the morning to warm it up certainly doesnt help mpgs either, nothing worse than cold motor,high idle and not moving for mpg lol.

Re: Hard time getting more MPG - 98' Sunfire
 

-trado,

I think those are his EPA numbers. I will admit it seems a little low given the spread of mine but for whatever reason, they rate these cars horribly. I know my car has never done as bad as the EPA combined even before I gave a crap.

they are big motors but they are still small cars. even in winter with snow and warmup times, I think I barely dip back into the 20s (MPG wise).

-to the OP,

you may want to start a gaslog. it will tell you what works and what doesn't at a glance. you can also see the wonderful rollercoaster which is summer and winter gas. mine is very obvious. I really haven't done anything crazy in a few years so the rollercoastering effect is really constant (at least I think so)

-2000neon,

are you a canadian as well? just curious.

Re: Hard time getting more MPG - 98' Sunfire
 

Yup, sorry I never really introduced myself at all in this forum, I'm canadian too, I live in southern ontario, about an hour west of Toronto. Our winter has sucked here so my gas mileage hasnt taken its usual hit, but definitely still seeing the effect of it.

Re: Hard time getting more MPG - 98' Sunfire
 

Hi there,

I have been keeping my fuel receipts (that show liters purchased) and keeping track of kms with my trip meter. I then take this info and have a found an online MPG calculator, so I enter the information and that's what it's giving me.

Re: Hard time getting more MPG - 98' Sunfire
 

Beef,

Thanks for the reply. I may look at getting some info from you about a frontal block-off, and lower pan.

I looked around at the gas stations here today, and from what I can tell there isn't any E10 in the fuels around here yet. I normally run shell (bronze) if I can. Our shell gas is infused with nitrogen apparently. Ethanol hasn't really made it to atlantic Canada yet from what I can tell.

What do you think about pumping up my winter tires a bit more? The sidewall max is 35. Would it hurt to put 40 in them? Do I risk a blow out?

Thanks again for your info!

Re: Hard time getting more MPG - 98' Sunfire
 

if you can go to a "hotter" thermostat, that would help. some manufacturers go with something less than 195*F. try a 195 if you dont already have one.

also, amsoil and mobile1 make a 0w30 synthetic. heck you could even go 0w20 in winter. i wouldnt run it in the summer however, but thats just me. your fuel gains will not likely be measurable, but you'll have quicker, better lube in the cold!

also, many credit and gas cards give rewards or cash back...not really fuel savings, but savings none the less.

edit: i just noticed your vintage and miles...you might stay away from 20 weight, unless of course, you're certain of no engine wear.

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.

Re: Hard time getting more MPG - 98' Sunfire
 

Hey guys,

Just an update here. I've recieved my new Turbogauge and installed it in the car last night. What a great little tool!

One thing i'm concerned about is my IAT. I've converted the car to a WAI, but the IAT is reading about 44C (roughly 100F) when the car is warm.

Does this seem cooler than it should be?

P.S. The air is being drawn from the exhaust manifold.

Re: Hard time getting more MPG - 98' Sunfire
 

I'd love to know more about your experience with the Turbogauge...keep us updated. I don't suppose that, in Chinese knockoff cloning perfection, it has an XGauge function like the Scangauge II and it's just not documented...

Anyway, 100?F is a good start. You might be able to do better. Can you post photos of your WAI?

Re: Hard time getting more MPG - 98' Sunfire
 

you may want to talk about delta. how much over ambient are you? if the delta is only 10 degrees, you may want to make a shield from window flashing or similar. if the delta is 60 degrees, you're probably fine. (degrees in F)

you don't want to get it set in the winter and then it top out at 250+ in the summer. I have heard that 180 is a good maximum temp to shoot for.

I may have to look into this turbo gauge. it looks very interesting.

Re: Hard time getting more MPG - 98' Sunfire
 

Here is a pic of my WAI. It's basically just 3 inch flexable duct. I cut a hole into the bottom of the air box and taped it up with heavy black duct tape. The air vent coming from the bottom of the car has been blocked with a cloth rag.

https://www.flickr.com/photos/7731002...928406/sizes/z

Re: Hard time getting more MPG - 98' Sunfire
 

If That link doesn't work try this one:

https://farm8.staticflickr.com/7048/6...8d2dd8ea_m.jpg

Re: Hard time getting more MPG - 98' Sunfire
 

First link is private. Second link is not very large:
https://farm8.staticflickr.com/7048/6...8d2dd8ea_m.jpg

So is it just the hose terminating at the manifold, or have you created any kind of additional stuff at the manifold?

Re: Hard time getting more MPG - 98' Sunfire
 

Sorry about the pictures. I'm just new at the picture posting thing. Yep, so far the duct is aimed at the exhaust manifold. I don't have anything else attached as of yet.

Re: Hard time getting more MPG - 98' Sunfire
 

Here is a quick look at the Turbogauge IV in my sunfire. I only have about 2 minutes of video (flickr has a time limit on vids) It gives you an idea of the interface. There is still lots more i'm trying to figure out on it.

https://flic.kr/p/byiMrD

Re: Hard time getting more MPG - 98' Sunfire
 

You shouldn't need the car running to use the Turbogauge...do you?

Ah, found a better resolution of your photo:
https://farm8.staticflickr.com/7048/6...8d2dd8ea_b.jpg

Re: Hard time getting more MPG - 98' Sunfire
 

To view the actual rpms, loads, etc. you would need the car running, but to view trouble codes, or the avg fuel economy, or trip totals you can just turn the key to the on position. When you shut the car off the gauge stays lit up for about 15 seconds and then shuts off.

Thanks for the better view of the photo!

Stew
"CanadianSunfire"

Re: Hard time getting more MPG - 98' Sunfire
 

why are you using electrical tape? I used the metal "duct tape". did you cover the original opening in the air box?

my engine compartment looks almost just like yours. I have a picture on my work computer of my setup where I was getting about 60 degrees delta. if I can remember, I will post it here on monday.

Re: Hard time getting more MPG - 98' Sunfire
 

Beef,

I just happened to have a roll of black duct tape kicking around here, so I just used that for attacthing it to the air box. The original air hole in the bottom is plugged with an old shop rag. Not sure what you really mean about "Delta".

Re: Hard time getting more MPG - 98' Sunfire
 

In this context, "delta" is difference between ambient and IAT. If your WAI produces a 100? delta, your IAT will be 170? on a 70? day, 140?F on a 40? day, etc.

Re: Hard time getting more MPG - 98' Sunfire
 

thanks THC.

that is excatly what I mean. sorry, sometimes my terminology can be vague depending on who I am around.

you may want to consider covering the original opening in the airbox with that same duct tape. the metal duct tape works pretty good.

the biggest thing is that the air coming past the radiator is blowing right on the manifold and dissipating the heat you are trying to suck up. you need almost a deflector shield for this. I know I have that pic on my computer somewhere at the house but I know exactly where it is at work. I will post a picture of it tomorrow.

basically you need a heat shield between the air coming through the radiator and the manifold (header, whatever) so you can gather the heat that it is letting off.

Re: Hard time getting more MPG - 98' Sunfire
 

it's monday, here is that picture I promised. I used flexible exhauste pipe and window flasing. it is only two sided. hopefully this makes sense.

notice how similar our engine bays are. it really is the same car.

https://i39.tinypic.com/10d9ro3.jpg

Re: Hard time getting more MPG - 98' Sunfire
 

Thanks Beef!

I'll look at changing my tape, and building a heat sheild with some aluminum. Was a bit dissapointed this morning. It's -11C here today, and my IAT was only 12C when the ECT was 75C. Looks like i'm losing a lot of my heat.

Thanks again for the tips guys.