One of the most commonly misunderstood forms of tuning is the chip tune. This form of tuning deals with actually altering the engine’s fuel and ignition maps as well as changing the timing of variable valve timing, rev limits and speed limiters. While this route can be a relatively easy way to improve performance, it can also severely compromise the engines reliability and stability.Conservative Factory Tunes
The reason the aftermarket has such success selling chip tuning services is because of the conservative nature of factory tunes. Fuel and air ratios are generally on the rich side, and ignition timing is generally retarded to help reduce chances of detonation. In addition, the redline and fuel cut of the engine are set at a level that the factory deems a suitable compromise between performance and reliability.
Tuning for Performance
The problem from the factory’s point of view, is that changes to the ECU tuning all have a potentially negative impact on reliability. Leaner fuel maps mean more power, but are far more vulnerable to a bad tank of gas or higher air temperatures. Tuned improperly, can cause immediate and serious engine damage. Advanced timing can mean more power, but also a higher chance of potential detonation. Should this detonation occur, the knock sensor may not be able pull out enough timing to protect the engine. In the case of a higher redline, the engine may very well be capable of performing at a higher engine speed. Though this also means higher levels of wear and a far higher risk of catastrophic engine failure if pushed too far. All these potential risks can mean serious engine damage, and this is why chip tuning will almost certainly void your car’s power train warranty. Tuning is all about compromise, and in the case of chip tuning, this compromise is usually with reliability and safety. While Factory Performance Parts and tuning are often done with warranty concerns in mind, this isn’t always the case with aftermarket tuning. Unless the tuning is done specifically under the approval of the manufacturer and labeled not to void the warranty, a voiding of the warranty is almost certain.