easy mpg increase?

have a 1992 olds 88 royale, and since gas prices are on the rise, i have been looking to dramaticaly increase the gas mileage with an easy fix.

i have been reading around and came across some home made water injection sites. then i got a really crazy idea. is it possible to increase my mpg, by taking a wet rag or something and placing it in the intake just before the air filter?

Or maybe run some kind of drip system onto the air filter itself? and then if anybody has any ideas on how to increase the mileage, i would greatly appreciate it. thanks for caring

I feel ya man, I really do. I just filled my '94 up and checked the MPG, its 15.84. My dad's F-150 4.6 liter V8 gets almost 18, so I'm pissed. later Duder.

Umm...yeah...you should be getting closer to 25mpg, more or less depending on how/where you drive. New, the 3.8 is rated around 20 city and 28 highway. When was the last time you did any serious maintenace (plugs, wires, filters, o2 sensor, properly inflated tires)??

As for non-maintenance upgrades, I've been planning a ram-air duct w/ K&N filter enclosed in a cold air induction box...more, cleaner, and colder air to engine means more oxygen for a fuller combustion of fuel and therefore an HP gain of 10-20.

You could always try a weight reduction, if your'e really desperate. Pull the extra seats, dashpad, carpet, headliner, spare tire, tools, grille, hubcaps (if not alloys), door panels (leave switches)... J/K tho :)

Umm...you could run basically anything made by Lucas or SeaFoam (both company's products acutally do what they say) to help get some gunk out of your engine. Or a bottle of chevron techron fuel system cleaner, it does what it says also.

One more thing, don't run gas from no-name stations or just crappy quality fuel in general--poor quality fuel won't burn as well as cleaner, better gas.

wouldn't a cold air system would decrease the mpg? that's what i heard.

Start with the basics. Plugs, wires, air filter, fuel filter, pcv valve, crankcase filter if your application has one. This will get you a noticeable mileage increase.

I changed the plugs two weeks ago. Umm, air filter is new, and the engine is running pretty good, a little slugish off the start but its what the 3800's do. Basically, I'm lost. The air pressure in the tires is good, probably a little over inflated even. I might have to go with Alibi's idea of weight reduction...jk. Though it would be kind of neat. lol. If anyone has any more suggestions I'll take them. My car doesn't have a catalytic converter, could that be it?

yes free flowing pipes would decrease your mpg.

by the way im trying something. i got the idea off some other websites, but what i did is i took a soup can, hooked a wire to it from an old fog lamp harness that isn't really being used, and suspended a wire from the top just so it wasn't touching anything. the i filled the can up with an electrolyte solution of water and salt. made a lid out of an old tuna can by cuting a slit out of the side. now when i turn on the wire harness, instant hydrogen on command. I don't have a way to feed it into the engine, so i just pointed the hole in the lid towards the intake.

i started her up, turned on the electrolyzer, she, did a lot of stuttering but eventually she settled down... i'll keep you guys updated on how well it works. oh and it gets really hot. so i actually put the electrolyzer can inside a larger can...

Seems like a lot of work. Good luck though.

wouldn't a cold air system would decrease the mpg? that's what i heard.


Hmm... Extra horses would prolly eat more gas so yeah, it probably would reduce fuel economy...but it would go faster :)

You didn't replace the plugs with Bosch, did you??? ACDelco's are 3800's friend. Also, it may be a good idea to replace your plug wires if they haven't been replaced in a while (don't buy cheapies, get at least midrange priced).

Anyway, have you checked for a vacuum leak? If you hear a whistling noise it is possibly a leak...spend two or three dollars on a foot or two of rubber hose suitable for vacuum lines and replace every bit of hose you can (don't worry about the plastic lines), especially if the old hoses are cracking.

Also, get a can or two of throttle body cleaner, remove the MAF screen, clean the throttle plate, remove IAC valve and clean that too. The build-up of carbon deposits would gum up those parts pretty bad if they haven't been cleaned in a while.

Vacuum lines have all beed replaced. The car wasn't in the best of shape when I purchased it. Put lots of money into it. The engine has had almost all the small parts changed out and what not. I'll have to try some of the Lucas or SeaFoam stuff mentionted above.

How many miles does the engine have? Has the timing chain ever been replaced? I believe 75-100k miles is the safe lifetime of the timing chain assembly.

A stretched timing chain would reduce MGP and would also cause hesitation and slow acceleration. If you do replace the timing chain and gears, replace the damper as well. One other thing to do while the front cover is off would be to replace and glue in (Jb weld or 2 part epoxy) the cam interruptor magnet to avoid a future code 41....

I'll give it some thought.

i've only run the electrolysis unit for less than 2 hours, and the electrodes have corroded away...

there's got to be a better way of doing this... seriously

heh when my tps was bad i got around 9 mpg right now i get 18 with the k&n i got from my moms gtp she did a cold air out of pvc cone filter im gona steal her car she pulls mid 13' s

I have found in the case of my 1992 98 (supercharged) and the galfriends 93 98 (naturaly asperated) , simular in the drivetrain to the 88, that too slow of acceleration hurt over all mileage. It seems that a bit more throttle than you would use with a carb'd car works the best. Weird I know but it shows up as about a two mpg difference (depends upon percent of city / steady state freeway driving) according to the computer.

These cars already have a cold air intake from the factory. Maybe not one of those polished units with a K&N, but it is a cold air intake in the simplest terms.

A full 3'' Flowmaster system on my 92 supercharged car DECREASED my overall mileage by about 1 mpg. Guess the factory knew pretty well what they were doing. Of course the flow master does sound a bit nicer :)

I agree on the timing chain, that will affect performance as well as mpg, especialy in city driving.

TPS starting voltages can also be tailored within a slight range which affects overall driveability more than mileage, unless the TPS is bad.

I average low 20's on both car in mixed driving, both cars will run 27+ on the highway. (previous owner of my 98 averaged 11 mpg, I changed NOTHING other than driving styles, the previous owner would idle the car for prolonged periods!?!)

As mentioned, plugs, Ox2 sensor, and checing for small vaccume leaks will probably do the most to increase your mileage as well as different driving habits.

My 2 cents :) David

do you think that if you use the cruise control to get up to highway speed would increase the mileage. i know my cruise control has kind of an aggressive attitude, but still, it would be designed for economy acceleration, wouldn't it?

I wouldn't waste my time messing with the cruise just to save a buck or two. I found that if you accel. rather quickly, the MPG is better. Not to soft and not balls to the wall.

Here is another power increase that I'm going to try, probably before the CAI

http://www.automotiveforums.com/vbulletin/showthread.php?t=558838

Better idle and more power on acceleration may help MPG, especially the idle. If not, then I doubt that a coil-style change would be detrimental to fuel economy.

i figured out how to keep the electrodes on my homemade eloctrolysis unit from corroding too quickly.... i discovered if you use pencils and shave the wood off most of the pencil, the graphite doesn't corrode and it lasts longer!! im a fweekin genius bwaby!!

oh and i have notice a slight increase in my mpg... i think i may try to come up with some kind of device to make more hydrogen and run it throught a hose, instead of just hoping the engine will suck it in...

i figured out how to keep the electrodes on my homemade eloctrolysis unit from corroding too quickly.... i discovered if you use pencils and shave the wood off most of the pencil, the graphite doesn't corrode and it lasts longer!! im a fweekin genius bwaby!!

oh and i have notice a slight increase in my mpg... i think i may try to come up with some kind of device to make more hydrogen and run it throught a hose, instead of just hoping the engine will suck it in...

i've been doing a little bit of research, and i found that if you use a performance aftermarket cone shaped cold air intake, not only do you get more power, you get better economy as well. just so long as you resist the urge to use this newfound power in rabbit starts. just drive like you normally do, and it should increase your mpg!!

my mom has a 01 GTP and she just changed her oil to the synthetic oil before she was getting about 16.5 mpg now she gets 20 she has a smaller pully on her supercharger cold air intake and a biggger pipe coming from the engine to the exhaust

how many mpg do you guys think i could squeeze out if i bypassed the ac pulley the next time i change my serpentine belt?

how many mpg do you guys think i could squeeze out if i bypassed the ac pulley the next time i change my serpentine belt?

ZERO, or at the least less than one tenth of a mpg - unless of course you use your a/c.

The reason? Well it takes a extremly small amount of horsepower to turn a pulley that is not connected to anything, as is the case when you do not have the a/c turned on. When you turn it on, a electromagnetic clutch engages the actual compressor which takes the power.

You could probably save a whole lot more by a watching the traffic lights, and speeding up when they are about to turn from a green so you can make the light on a green and not have to waste the fuel with a stop and restart.

Along with that, if the light does turn red, get your foot off the throttle as soon as practical rather than charging the light and hitting the brakes at the last miniute.

You should be able to squeek out close to 30 on the hiway and around 20-22 average between city and hiway with the upper teens for all city driving. Unless of course you spend a exceptional amount of time idling, in which case you should shut off your engine.

Anything less than above mpg, I would think that you either need to fix your car running problem or adjust your paticular driving style. Or maybe a bit of both?

One last thought - you could bypass your power steering pulley and save a bit of fuel, but it will make it a bear to drive. But I do imagine that you would probably see a .2 to .5 tenth improvement in your mpg.

Just my two cents ~ which work well with my Olds 98's / 3.8's ~ David

hmmm... well, my compressor clutch doesn't even work in the first place... in fact i think maybe i should take a look at that when i get home tonight... if it's kind of difficult to turn i may just take the clutch out completely. that will keep it from being difficult to turn (i hit something and it seized up or sumthing...

Sounds like a good plan, if your a/c clutch is always engaged then you are definatly wasting a bit of fuel that you could save.

David

what about the fuel filter? can changeing a dirty one that increase you mpg? if so why would it increase the mpg...

Yes, nasty fuel filters do impede your MPG b/c less fuel is able to travel to your injectors. As you press the accelerator more to get push fuel through the crap in your filter, you not only wear the pump faster, but fuel in spurts as backpressure in the lines force the fuel through the nasty filter after sufficient pressure is built. A clean filter will allow constant flow of fuel to your engine, which can maximize its use without being starved or flooded by fuel coming though a nasty filter.

now i've been looking at getting an aftermarket air filter, but i would like to know. i have a cavity that could fit the air filter right above my charcoal canister. the only problem is that it is kind of warm. without a box to seperate the air filter, will i be able to increase the mpg using the warmer air, even if it isn't hot... just u no warm?

You could get a K&N filter that would just drop into the stock air box. Or, you could get a K&N cone filter and attach it on the end of an L-shaped pipe out of your throttle body (ram air, basically). Although the space would be greatly improved by going the second route (after removing the stock air intake), you would be sucking in warmer air. An aftermarket filter, such as a K&N cone filter, would probably still help mpg and HP although it would be sucking in more warm air than the stock system was (had that annoying plastic "snorkel"), unless you box it off to create a CAI box...which is really pretty simple to do if you don't mind using cardboard for a while ;)

on the front of the throttle body, there is a screen that supposedly is suposed to swirl the air a little... I was wondering if i ditched it would the less air resisance allow for better flow of air resulting in better mpg, or would the lack of swirl negate the effects of less air resistance?

i know it sounds like i'm beating a dead horse, but i pay almost as much in gas as it takes to travel to work to make that money in the first place. but i love my olds and i just want her to run better. thank you all for answering all of my questions, i gr8tly appreciate it.:)

The screen is actualy there to smooth out the airflow. You want to avoid turbulance in the intake air stream with a Multi port fuel injected engine.

If you had a carb'd engine then you could install a screen under the carb base to help atomize the fuel, with a performance loss in top end power though. Doesn't work this way with FI though.

How far do you drive to work? I wonder if a block heater would be a good idea to get the engine up to operating temp as fast as possible, IE when the engine is cold you are running on a enriched fuel map in the ECM ?

David

Nope, don't take the MAF screen off. Also, don't bother with buying one of those turbonator or tornado air intake inserts. Any swirl those create are negated by the presence of the MAF screen.

Basically, your best bet for good fuel economy is a well-maintained, clean engine and proper suspension/decent tires. Thats about it. That and not driving like a maniac helps a bit too ;)

ok, so, how do i clean out the inside of my engine, i really don't want to have to take the cylinder head off...
just to note this, i have taken off the fuel rail and injectors and cleaned them up, but if you stick your finger in the injector ports a grimy gunk crap comes out....

Seafoam. Go to autozone and ask or just look for it.

i don't know what else to do... i can't keep up with the cost of putting gas in my car... ... o and happy mothers day to all you ... mothers... out there.... lol

I took the screen off my maf yesterday and so far nothing has happened as of problems. i did notice slightly better throttle response, but i haven't been able to determine the gas mileage yet.

I would put the screen right back in if you didn't destroy it taking it out. There is a small increase in the CFM capability of the TB without it but the downside pretty much negates it. Besides, giving the engine more air will not increase MPG.

Without cracking open the engine there is very little you can do to a *new* engine to increase MPG. For older cars a full tune-up is the one of the best things you can do.

Good read: http://www.fsec.ucf.edu/Pubs/energynotes/en-19.htm

hey you.... keep an open mind here. if we're going to get through this gas shortage thing, we gotta start doin something about it.

o and as for more air decreaseing mpg, thats a myth. think this through logicaly as you read this. say you have a set amount of fuel, if the is fuel injected in predetermined amounts more oxygen allows the gases to burn more completely and delivering more power. if you drive conservatively less fuel is needed to keep the car going due to the fact that more power is being produced. what you hear about it decreasing mpg, is about people who want to go faster, not improve their mpg, so they accerate hard, brake hard, and thus waste more gas. ok, so i know 2-5 mpg increase doesn't sound like much, but do the math.

18 gallons per tank * 2 mpg increase = 36 right? 36 extra miles to the tank, and say i go through about 20 tanks a year. 720 extra miles. at an average of 25 mpg that's like 28.8 gallons saved. at $3.00 a gallon, that about $86.40 saved.

i can think of a lot things i'd rather spend that $86.40 on than gasoline.:iceslolan

Not sure if you're referring to me but I didn't have a closed mind at all when I posted that reply. As for the MAF screen, it's important that it stays intact. The purpose of the screen is to make the air laminar before hitting the MAF sensor itself. Without it the turbulent air may make its way around the sensor and result in a lean condition. Most see this happen at idle and report a rough idle as a result. You're far from the first to try it.

I get what you're saying but you're a bit off in your analysis. Lets assume pulling the MAF screen did give you additional airflow. First the MAF sensor will tell the PCM that you're getting additional air and it will then increase the pulse width of the injectors in an effort to maintain stoch. That failing, it will then be caught by the o2 sensor which will do the same. This is how power is increased. Air does not = power. Fuel does not = power. Air + Fuel = power. If you had a way to control the pulse width of the injectors you could do what you're saying and save gas. They do it in racing all the time when they're running low on fuel. It drastically decreases power and risks burning up an engine, but sometimes just finishing is most important. You, however, do not have that capability.

What you'll need to change is the efficiency of the engine, not necessarily the power produced. Better efficiency will generally yield better power, but it doesn't always work the other way around especially in the way you're describing.

One big thing to keep in mind was mentioned above. Air + fuel = power. Since the PCM will command the same ratio no matter what power you're making, simply adding airflow will ALWAYS cost you more fuel, even if you keep your foot out of it. The only difference is you may be making the required power without your foot being as deep into it !BUT! if you do nothing for the efficiency of the engine, the power required to maintain 60mph will ALWAYS require the same amount of fuel and air. No matter if you make it with the foot to the ground or barely tapping it. The only way you can keep your foot out of it and still maintain 60mph is to change the gear ratio or tire size. This is why the Overdrive feature was added.

Hope it all makes sense.

can having bad struts cause bad mpg just wondering i have 4 new struts for my car i jsut have to put them in car kinda bounced errrmmmm every where hit a bump bounce down the road untill i stoped lol its pretty bad gives me and my friends something to laugh at

Well, I would imagine that there would be a slight increase in fuel usage at say a fixed hiway speed as it would tend to interupt the airflow and also the bouncing could raise the car and therefore pack more air under it which would cause more drag on the rough undersides. ??

In the same line, Raz - If you were to lower your car, along with adding a large front airdam that has some aerodynamics you should see a increase in MPG. Same thing with having a window down / open that will decrease your MPG. Sure is not fun though to drive around in a car with no a/c and the insode temp at 140 degrees with the windows up!

Just more thoughts on easy ways to increase mileage.

hey i thought that gm made that learning thing with the brainbox din't they? doesn't it like control the pulsewidth from the sensor inputs?

if not, then could i somehow change the pulse width?

here are some good links that may proove my point that a cold air intake does infact increase fuel economy

http://www.usdieselparts.com/pages.cfm?ID=117
http://www.knfilters.com/feedback13.htm
http://www.autoanything.com/air-intakes/50A5A115A1.aspx
http://www.aa1car.com/library/gas805.htm
http://www.wikihow.com/Save-Gas

Which is why your CAME FROM THE FACTORYwith a cold air intake. But not as a fuel MPG improver, but mainly as a performance enhancer.

A aftermarket LARGER cold air intake wil not improve your fuel mileage on a stock engine though. REGUARDLESS of the "advertising" claims. This has been proved many times over.

But - it does open up the intake tract and makes the engine sound better if you like that sort of thing - and doesn't a louder engine make more horsepower simply as a function of making more noise? NOT!

As to real increased horsepower with a aftermarket Cold air intake... NOT at your normal cruising speeds. You may gain a slight increase in horespower at high rpm, but then running your engine at those higher speeds kills your fuel mileage.

D

ok imagine it this way, is it easier to suck a milkshake through a coffee stirrir, <1/8 " or through a straw that is 1/4 inches in diameter?

takes more energy to suck it through the coffee stirrer... correct? if not explain to me why this is not the case.

if it takes more energy to suck it throught the small one, were do you think that sucking energy comes from? i can tell you it doesnot come from pixie dust.... it comes from the negative pressure caused by the pistons set in motion by the fuel. the leeching affect... easier to suck it in, the less energy is dedicated to sucking it into the intake.

ok imagine it this way, is it easier to suck a milkshake through a coffee stirrir, <1/8 " or through a straw that is 1/4 inches in diameter?

takes more energy to suck it through the coffee stirrer... correct? if not explain to me why this is not the case.

if it takes more energy to suck it throught the small one, were do you think that sucking energy comes from? i can tell you it doesnot come from pixie dust.... it comes from the negative pressure caused by the pistons set in motion by the fuel. the leeching affect... easier to suck it in, the less energy is dedicated to sucking it into the intake.

Ok, well your reasoning would only be 100% true if you were running the engine at the highest operating RPM. AT NORMAL RPM LEVELS such as cruise and acceleration, the FACTORY COLD AIR INTAKE sytem is not the restricting intake component. It is the intake valves.

However, as stated previously, if you increase the RPM potential of the engine, such as changing the cam, etc, then the stock factory CAI MAY become a restriction, but ONLY at those higher RPM's, NOT at your normal cruise or accelerating RPM's.

Do you normaly run your engine at 4500 rpm or more? Hardly. And if you were, then you kill your fuel mileage. However that is where the aftermarket CAI's come into play with the ability to pass more air flow AS DICTATED by the HIGHER rpm.

No offense Raz, but you said it yourself, you wanted to dramaticly increase your fuel mileage, but not spen much money. You can not get there from here with those restrictions. Yes, you can drop the final drive ratio, but if you were to save only the theoretical $85 a year (once again your calcalations) with a two MPG increase, it would take you more than 10 years to repay the cost of changing the final drive ratio.

If it was a easy as flipping a switch or removing a screen the factorys would do it, especialy now that fuel is at a premium price.

Now, don't take offense, but I'll bet you that $85 that if I was able to observe your driving habits I could probably point out where you could save more than that by simply changing your driving habits. And secondly, if it really comes down to $85 a year, then to be honest and please don't take offense at this, but you can't afford to drive a car. It costs more than that in other costs such as repair, insurance etc.

I agree totally with you that there are better things to do with one's money than spend $3.50 a gallon for fuel, but this is the reality that we ALL were WARNED about in the 70's. It is also why you could buy a new Honda Civic in the early / mid 80's that was rated at 67 MPG hiway, YES 67!!! abd 55 MPG around town. YES 55!! You had to shift it yourself, it was small, and had 47 hp, with a top speed of 85 mph, fast enough to get you a ticket in any of the 50 states. Or, if like me, you prefeer to drive and support America, a Diesel Chevette at 55 MPG hiway. BUT like most Americans, I chose to drive a less efficient vehical so they stopped making that type of car, at least in this country.

But remember, we are dealing with a limited resource as we learned over 30 years ago. Guess the lesson was forgotten.

David

but you fail to realize that i love my olds.... i don't know about you but simply switching to a different car is not something i really desire to do.

i read something about install a vacuum gauge to measure intake manifold pressure and then using it to help adjust driving habits, by watching the load on the engine or something.... is this true?

one last thing what if the auto companies and gas companies were working together, cuz everyone knows they are. it's worse than the enron scandal.

Razr - for all of the discussions, I sure agree with you on the Olds - it is why I keep mine and just pony up the $$ to keep it fed. (I pay for the galffriends fuel also) Double $$ $$ lol Of course I had to give up any sort of a vacation this year because of the fuel costs... so I sure feel the pain also!

David

I realize that the gas prices hurt all of us in the pocket book, but the way I look at it, its gonna happen. I'm not going to stop living and enjoyin my life because of gas.

i don't really let it bug me, i just love to tinker with cars and fuel economy is my project.