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Chipping your engine

I was visiting another car site, and there was a google ad for a company that sells replacement chips for the ECU that supposedly increase horsepower AND gas mileage without sacrificing emissions. (From the installation instructions it sounds like they are going to flash the ECU and overwrite it’s original settings.)

Their explanation for why the manufacturer’s settings don’t already maximize fuel mileage and performance is not very clear, and instinctively I know that you can’t get something for nothing – more power and more efficiency and less emissions all from the same chip sounds bogus to me.

Is it?

In my opinion it’s bogus.

If a company could actually manufacture a chip that is as effective as they claim, they would be able to make a lot more money selling it to the automakers rather than individuals.

It is obviously a case of when something sounds too good to be true (it ain’t true).

In some engines a chip flash / replacement chip can work wonders, but not on both power and efficiency. Engines are a pretty simple equation when you break them down.

Air and fuel go in, power and exhaust go out. If you want more power, you need more air and fuel, which means you’re. . using more fuel. If you want better economy, you need to use less fuel, which means you’re reducing power.

That’s a very simplistic explanation but it works in this case because you aren’t changing anything about the engine itself. If you’re changing anything you’re only changing how much air and fuel go into it at a given time.

The reason you can sometimes get more power from chipping an engine is that thanks to environmental regulations and (lately) the price of fuel, a car maker is more likely to set the engine to operate using less fuel, which means less power. So if you want more power, you can chip it, but you’re going to sacrifice the fuel economy built in to the original programming.

Automobile manufacturers go through a lot of effort to design the software in the PCM to provide power, fuel economy, low emissions, and good driveability. The engineers steer the program away from conditions that would affect the longevity of the powertrain at least until the warrantee has expired. Then, they test the vehicle in all sorts of conditions to make sure there are no unforseen conditions and if there are software bugs.

You have to ask yourself if the chip manufacturers have gone through the same quality assurance steps. You might get more power by exceeding RPM limits; more economy by leaning open loop parameters to the detriment of the valves, detonation, stumble, and hesitation. When you think an accessory company can out engineer the manufacturer, that company has got to have some great credentials. Also, check for the warrantee from the chip manufacturer if their chip burns down your engine or smokes the transmission.

Good luck on this.

Oh, I’m not touching my ECU. I’m pretty sure this is bogus, but I’m curious if anyone has tried them and they really work or not. Supposedly, the new chip adds more fuel when you accelerate (so more power) and uses less fuel when cruising at highway speeds (more efficient) while maintaining the proper stoichiometric ratio.

What I can’t figure it, who would read that spiel and assume that car makers don’t know the proper fuel/air mix, or haven’t figured out that you need less gas when cruising.

IMHO, the menu for what “re-chipping” can do is…limited.
Do you want more power, or do you want better fuel economy?

Pick one.
No menu substitutions!

The Fusion is OBD-II compliant, any tuning of the ECU will be done with a laptop or hand held tuner, not a “chip”. The manufacture?s have CAFE standards to meet, it would behoove them to tune the car the for optimal fuel mileage from the factory. These “chips” you see being sold for around $20-$70 are simply two cent resistors are pure scams.

The sure way of doing this is with a laptop and a dyno, where you can watch power, emissions, and fuel use as various parameters are changed. There are some brand-specific cases (like BMW and the Dinan performance company) which do offer legit engine modifications for significant $$. However, 99% (including ALL ads with listings for multiple brands of cars) are bogus.

A lot of times people will buy a chip at the same time they buy an intake, headers, exhaust, and sometimes a turbo. Then they’ll go around thinking the chip helped in the overall powergain. Which it did, because it’s designed to account for the other stuff you put on that the factory engineers didn’t design their chip to handle. But if you just do the chip alone, it usually doesn’t do anything except in certain situations.

You’re right - I should have added “but you won’t see much of a change” to the first sentence. Doing all that work to a stock car will normally yield very little in power or economy.

There’s enough people out there that believe in these “magic devices” to make the purveyors of them a lot of easy money. People really don’t stop and realize the amount of money and effort that automakers put into optimizing power and drivability against emission and fuel efficiency requirements. Doing so is a complex technical problem, and they do it as best possible.

There are even those that believe there exists a conspiracy by manufacturers to NOT make 100 mpg cars. The problem is complcated by things like the placebo effect and the “Smokey Yunick secret engine”. Smokey Yunick was a legit guy in the automotive world, but he was also a P.T. Barnum showman of the highest order. A true self promoter. And while some claim to know his secret, and even give plausible technical explanations, nobody has ever successfully recreated his alleged magic engine.

There’s no magic, only the same old physics with evolving technology like direct injection to sqeeze as much energy out of each fuel droplet as possible. But there isn;t much left to get, as evidenced by the completeness to which the gas is already burned (as seem by emissions results).

Usually you replace the programming in order to get an increase in HP or economy.

It works with turbo charged cars like Subaru and VW with a decent amount of reliability. However a normally aspirated engine it is much more difficult to tweak much power or economy out of them.

I’m currently considering doing this and I saw an ad for a chip at The chip is adjustable and the co offers a satisfaction guarantee so it seems there’s nothing to lose. It adjusts from additional 4 hp to 35 hp, and, as my friend, a service writer, told me, the more hp gain with these things, the less fuel efficient your car becomes. Sounds pretty cool and it is $89.99 plus $10. shipping.

Guaranteed! (bogus, that is).

First, just because they offer a satisfaction guarantee doesn’t mean that they’ll actually do anything beyond “Oh, sorry dude. That sucks.” when you’re not satisfied.

Second, as noted several times above, unless you buy a bunch of other parts and the chip you get is meant to work in concert with aftermarket parts, you might as well buy a 4 foot kombat wing and a wide body kit, because they’ll both do just as much to make your car faster, and at least you have something to look at with the body mods :wink:

They can offer a worthless chip with a guarantee, honor the guarantee, and still make a bundle. 90% of the buyers will either think they’re getting a boost (the placebo effect), or will be too lazy or embarrassed to ask for a refund. 10% refunds? No problem! $90 in, $10 in parts (max), $9 in refunds. $71 profit!

Placebo effect? When did Car Talk open up a medical research site?

Placebo isn’t a medical term. Besides, I could swear that the rear spoiler actually made my '72 Vega go faster.

Placebo effect - when somebody spends $90 on something and convinces themselves that the car runs better, even with no change at all. Happens all the time!