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After market gas savers

Shop at a grocery store that gives gas discounts. That’s the only aftermarket gas savings that really works.

I agree with jtsanders. My grocery store has given me coupons good for 20 cents per gallon off on a gallon of gasoline for up to 15 gallons at Speedway stations. These stations are competitively priced in my area. In my son’s area, the Kroger and WalMart have pumps with discounts for their customers.
Gasoline is below other items on the list for automobile expenses. Depreciation, interest on the loan, and insurance are high ticket items.
Nissan makes a pretty reliable truck. If you keep up the routine maintenance, you may be better off than some economy car that requires an expensive repair. Furthermore, pickup trucks don’t seem to depreciate as fast as automobiles–at least in my area of the midwest. In the long run, your wife’s purchase may not have been a total disaster.

One more note–back in the 1950s, the Borg-Warner automatic overdrive was an option on many cars. I read a calculation that the car would have to be driven more than 100,000 miles to make the option pay. At that time, gasoline was about 25 cents a gallon and the life expectancy of a car was 100,000 miles. On the highway, the overdrive might increase gasoline mileage by 4 mpg. In city driving, the overdrive car might not do as well as the car without the overdrive, since the overdrive wouldn’t engage until about 30 mph and the axle ratio was numerically higher (geared lower) for the overdrive equipped cars.
Save your money. It is doubtful that the gas saving chips will do anything except rob your wallet of gasoline money.

I’m very sorry how harsh I’m gonna sound.

at about 16miles per gallon average, and driving like 2000 miles a month (which is way above average US monthly mileage), the cited gas price difference will come to about $125 a month more in fuel expenses.

if this difference means the OP and his wife can’t make the truck payments, I have to conclude they made a poor judgment call purchasing a vehicle they can’t afford.

trade in and cut your losses.

To answer the OP question, aftermarket gas price savers devices are usually scams, but in this case, an aftermarket chip intended for a high performance vehicle (like this particular truck) MAY improve fuel mileage. However, OP MUST do the math this time, research on how much fuel this chip can save (not taking the manufacturers word… find some reviews around the 'net), calculate the expected fuel savings and compare this number with the chip’s price.

Remcow’s suggestion sounds good too (as well as his gas guzzler comment)

I bet the fuel savings will not be worthwhile.

Any ad that claims a chip is going to improve HP, performance, and increase mileage is a scam. Otherwise, that chip would be manufactured on the cheap and installed on the assembly line when the vehicle was built.
Your best bet is to sell the truck and find something else but a gut feeling tells me you’re upside down on this thing.

What I would ask the OP is this. You state your wife made a little mistake and bought this truck. Where were you during this transaction?

Well, thanks for all the kicks. This is a mistake I won’t make again. Since most of you lack any perception or sense of humor, the question was, “I’ve been out of the business a long time. I don’t know anything about this sort of technology.” Can it work? I assumed these vehicles have some sort of generic chip for driving anywhere. What if a driver drives back and forth to the A&P? That’s one situation. Another drives long distances on the interstate at 75. Different world. Of course we can afford gas and truck payments and the price and mileage were so low there was no way we could be upside down. Thanks for the grocery suggestions. We get up to 10 cents from Fry’s and up to A DOLLAR per gallon from Safeway here in southern Arizona. What was I doing when my wife was buying it? Right there watching. I love to drive it. Of course I hate to try to park it, but that’s another story. Did any of you ever try any of these things? Sorry. It was 5.6 liter, about a 350 old style. OBTW, we actually do own an Altima, too.

I agree that any chip that claims to improve power and increase mileage and still meet emission standards is a scam.
However, any chip that that claims to improve power and increase mileage, but at the cost of violating exhaust emissions, is now talking a very different conversation. It is doable.

@azwhiz:

"Since most of you lack any perception or sense of humor, the question was, "I've been out of the business a long time. I don't know anything about this sort of technology." Can it work? I assumed these vehicles have some sort of generic chip for driving anywhere. What if a driver drives back and forth to the A&P? That's one situation. Another drives long distances on the interstate at 75. Different world."

Although I don’t care for your insults, I’ll continue to offer advice. On any vehicle as new as this truck, the engine computer is intelligent enough to adjust for different types of uses. There is no specialized chip that will make it better for a single type of use. The one type of use that could justify modifying this engine would be on a race track.

We’re people having a discussion. Similar to what you might find if we were all standing around in a room, you will find the topic of conversation is fluid, and people will often offer answers to questions you didn’t ask. That’s the nature of conversation. It doesn’t mean we “lack any perception or sense of humor.” In fact, I think if you stick around, you will find the opposite is true. It means we think you can benefit from advice you didn’t necessarily ask for. Perhaps, if you want to limit the conversation to one particular question, you should only offer information that is directly relevant to that question.

I agree that any chip that claims to improve power and increase mileage and still meet emission standards is a scam. However, any chip that that claims to improve power and increase mileage, but at the cost of violating exhaust emissions, is now talking a very different conversation. It is doable.

I don’t think so. The chip is NOT changing the programming…all it’s doing is changing the parameters of the program. It’s a very very very narrow range of parameters that can be used and still allow the car to even run.

The factory computer does an excellent job of controlling the engine for all normal driving conditions while meeting emissions requirements and maximizing mpgs. Any ‘chip’ from a company that sells chips for every car made is a SCAM, guaranteed. The only possible improvement is an expensive trip to the engine dyno, with a computer and a laptop to carefully reprogram the engine control computer. This is done for high performance machines, but costs hundreds of dollars. Any small fuel economy gains from doing it would likely never pay off the costs.

And your ‘humor’ was not apparent, it’s very hard to separate joking from facts in a discussion like this. We have dealt with folks that could not afford the car they just bought. No way for us to know your situation.

Either grin and bare it or sell the truck and buy a compact car. You either need a truck for your business (where it MAKES money for you) and keep it or you buy something economical, like a Sentra, if the price of gas is that important to you.

"any chip that that claims to improve power and increase mileage, but at the cost of violating exhaust emissions, is now talking a very different conversation. It is doable"

One way to raise MPG would be to force the engine to run slightly lean most of the time.
This graph shows that fuel efficiency peaks when lean of stoichiometric:

Two problems though.
Excess oxygen in the exhaust would keep the 3-way cat converter from removing NOx pollution.
The cat converter needs the mix as close as possible to stoichiometric.
Major (and illegal) changes needed to the software in the ECM to run closed loop lean
and skip the catalyst efficiency test.

CircuitSmith and MikeInNH:
I will respectively still stand by my statement that if you’re willing to forgo emissions, then it’s possible to increase both power and mpg.

In the early 70s I took an internal combustion engines course. At that time, all car manufacturers ran their engines about 10% richer than stoichiometric. That’s where mpg peaked. Power reached a peak around 16% richer than stoichiometric. The main reason why the richer mixtures provided more power and mpg was because there is so little time to properly mix the air and fuel in a combustion chamber, that inserting extra fuel caused more of the precious oxygen molecules to have an adjacent fuel molecule to burn with.

We had an engine dynamometer in that class. We first had to do the textbook math to prove the above, and then we verified it on the dynamometer.

In 1975 when catalytic converters came out, manufacturers were forced to go to a stoichiometric (chemically correct) mixture. Power and mpg dropped. For a few months, I had a small business on the side where I’d drill out carburetor jets on friend’s cars. The average jet diameter shrunk about 0.002" from 1974 to 1975. I drilled them out to the previous sizes - benefiting both power and mpg - to the delight of many of my friends.

I got the above idea from reading an article in an automotive trade rag describing the same procedure, and based on what I had studied, it made perfect sense.

Today’s engines have better combustion chamber design, and fuel delivery - which means the 10%/16% numbers which were optimal back then are likely much lower today.

One thing that was vividly definite was going leaner than stoichiometric hurt both power and mpg.

"I will respectively still stand by my statement that if you're willing to forgo emissions, then it's possible to increase both power and mpg."

Maybe it wasn’t clear that I was agreeing with this part.

"One thing that was vividly definite was going leaner than stoichiometric hurt both power and mpg."

There’s lots of literature out there that disagrees with this. Just google “specific fuel consumption vs fuel-air ratio.”

This works! It makes money for people who sell it and do not promise too much legally. As to the people who buy the stuff I rarely see any benefit for them. In some states the exhaust changes will get you in trouble. In others the chip change can be detected and you get fined and refused inspection. Mostly California but some other states as well.

Joe Mario,
At that time it was a nearly correct issue as carbs did not mix air and gas well. All engines now use injectors with very fine particles of fuel at high pressure, thus makeing the mix entering the chamber much closer to ideal than you were taught. Carbs cannot provide the micro size droplets that mix instantly when placed in high turbulent condition next to the intake valve. It really is a new tech as much as you dismiss it. These engines today using odb2 are at the right curve nearly all the time. As to milage and power you just miss the mark You really cannot increase both today. Carbs were so inefficient sure that could happen because they were so touchy anything you did to them was good or horrible.

I don’t know if this will help with this tangential debate, but one version of the 6th generation Honda Civic, the Civic HX, came with a special lean-burning engine and CVT transmission, and it got better fuel economy than other versions of the 6th generation Civic. Except for the CVT tranny, it was just as reliable than other versions of the Civic. I’ve seen a couple on the road recently, although one was a stick shift version.

The other issue in the fuel mixture debate is the flame temperature. Stoichiometric or leaner mixtures run hotter than fuel-rich mixtures, and in more rudimentary engines, like my old Honda 305 motorcycle, you risked burning a hole in a piston if the mixture ran too lean.