Back in the grand old days of automobiles, engines had carburetors. Repairs could be made with chewing gum foil and twine. The problem was you needed to make these repairs often. ECU’s eliminate the unreliability but we lost that simplicity of repair.

There is something wonderful about turning a couple of screws and getting a noticeable change in how your vehicle runs, altering the idle point, getting the fuel spot on and having a blast right after it’s adjusted. It’s a great part of the automotive experience – until you need to adjust it again… and again… and again.

One of the best parts of modern fuel injection is the “set it and forget it” peace of mind it offers. That’s not to say a carburetor couldn’t be stable like that – they just weren’t more often than they were.

So how do you get back some of the magical feelings of adjusting your vehicle to make it run better than the factory settings? Some turn to piggyback programmers, while others use experts who can alter your factory ECU.

ECU Tuning

ECU tuning is the art and science of cracking the code that the factory installs in your cars’ brain and giving it an upgrade. Tweaking your ECU means removing things like low RPM power restrictions, closed loop fuel maps, error codes when changing parts, and a slew of other options. It enables you to take a lackluster vehicle with twitchy throttle control and turn it into that smooth powerful monster you expected.


A typical reprogramming or “reflash” of your ECU can vary pretty wildly in price. In researching this to make some changes to our Jeep Wrangler, we found that costs ranged from $200 to almost $500 for the work we wanted. We found out right away that the credentials of those who are offering to do ECU mods can swing wildly; there are people who purchased an ECU programmer and do this as a hobby, and there are professional shops with years of experience. You can get a good setup from a home hobbyist but as the old saying goes Caveat Emptor. (Let the buyer beware.)

Finding the Right Place

We started by asking shops locally who they turn to, then we talked to owners who have used tuning shops until we found one that kept popping up more than others. More on that in another article.

How to Make Your ECU Better

Here’s what we plan to do to our ECU to improve our Jeeps lackluster throttle response, overbearing traction control, and torque limitation.

The traction control is limited to 56lb-ft under wheel slip conditions. If you have tried to leave a snowy parking lot and wondered if you were ever going to move this is why. The engine is being told to produce next to 0 power so the tires can get traction. Add to this equation larger wheels and tires and the situation is even worse.

Same thing with stability control. The calculations are based on a percentage of wheel speed difference, body lean, etc… With larger wheels and tires this split point is reached far earlier than with smaller tires causing the stability control to kick in more aggressively.

We are also going to work on the stall control and several smaller items to make the Jeep operate more like a cable throttle and non-computer controlled driving experience.

Is ECU tuning right for you?

That is a tough question to answer. Much like the age-old question of “Do I need to regear with larger tires” there is no one-size-fits-all response. Your bench-racing buddy might tell you there’s gobs of untapped performance, but that isn’t always correct. If your vehicle has factory limitations built into it creating a driving experience that’s less than perfect, ECU tuning is a very effective way to get the car or truck you expected. It can also boost your vehicles performance levels if you’re feeling like you’ve outgrown the power it produces. If you have performance upgrades, sometimes ECU tuning can make huge driveability and performance gains and sometimes it is a necessity if you don’t want your engine to throw codes or to implode from poor fueling etc…

If you are totally happy with your vehicle and don’t want to mess with any item and never change a part from stock, you might just want to let your ECU do its own thing. If it ain’t broke, don’t fix it.

Have you tinkered with your car or trucks ECU? Would you? Let us know in the Comments section!







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William Connor

As the Editor, William is responsible for all the good, the bad, the ugly and the indifferent that happens at 4WAAM. William brings a wide range of experience to this role. He also wields a freely shared...

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