Alex E. / Total car diagnostics (2013). “How To Program Car’s ECU (Guide to Car Tuning / Chip Programming)“. http://www.totalcardiagnostics.com/support/Knowledgebase/Article/View/55/0/how-to-program-cars-ecu-guide-to-car-tuning–chip-programming
First a basic beginners guide introduction into world of car tuning and what you need to know:
The ECU of your car is like its brain. For your car to deliver its best performance you have to keep it in a fit condition at all times.
This is the only way to ensure that you get the best in both drivings as well as handling. Modern-day cars do not have manual controls. Nowadays sophisticated technology is being incorporated in the form of computerized controls that guide and ensure Engine performance.
Whenever you make a physical intervention the data pertaining to such intervention gets recorded in the memory banks of your car’s computer.
The computer uses the mapped data to work out the optimum control conditions in which the engine should function.
The ECU shuffles through the tons of data that come to it in the form of readings to decide the course of action that should be taken by the engine to ensure an ideal drive. The ECU tells your engine not only what to do but also how to do it. Thus the ECU in order to make accurate diagnosis on engine control utilizes stored data.
Even though you have made modifications in your car, the ECU still continues to get an input of the old data which is stored in it’s memory. This old data no longer is credible as it pertains to conditions that existed before the modification.
The input data to the ECU should pertain to the post modification situation of the components and parts introduced, while making the modification. This means that you have to erase the old data from memory and new data pertaining to post modification should be logged into the ECU memory by mapping in new readings. This is the reason why ECU resetting is essential for optimum performance after any modification has been carried out in your car.
The moment you have carried out the modification you should purge out existing data in your ECU’s memory. You should then feed in fresh data pertaining to the conditions that have come into existence post modification. The ECU has to operate on the newly acquired data as this new data reflects the true conditions post modification.
You should be well versed with the vital art of resetting the ECU of your car. You have to let your ECU adapt itself to the new situation arising out of the modification. Allow your ECU to relearn and perform.
Now therefore the step to be performed is to purge the old data and reset your ECU. Doing this allows it to adapt itself to new parts and efficiently perform post modification also. To reset the ECU you simply have to unplug the negative battery cable connection. Theoretically it is best to leave it in this disconnected condition for as long as you can. Practically leaving it disconnected overnight is more than enough.
After having left the cable disconnected for sufficient time you have to connect back the cable. Start the car and keep it running so that it warms up. This would not take more than 10 minutes at the most in summers. Once you have done this you have accomplished the ECU resetting. Shut off the engine.
You can now use your car whenever you feel like. ECU resetting is over.
You should remember a few points when doing the ECU setting. One important point that you should remember is not to reset ECU when using fuel additives or different octane fuel than you normally use. The idea is not to reset the ECU when using anything in your car that you normally don’t use. You should prepare the ECU to get adapted only to the conditions that it would normally encounter. This would also reduce the number of resets you will have to do to the ECU.
However if you are going to change the operating conditions on medium or long-term basis then you should reset your ECU. One such instance could be when you think of boosting octane.
Resetting the ECU when you choose to boost Octane becomes necessary because your ECU has a memory bank for octane.
This means that if you’ve been using lower octane, the response of ECU will correspond to lower octane with the booster matching lower octane performance.
The ECU response will continue to correspond to lower octane even though you have started using higher-octane fuel. This is because the ECU has not been reset for higher octane. Thus even though higher octane is in actual use, the data in ECU memory still corresponds to that of lower octane. This mismatch affects performance, as you are unable to derive the benefits of boosting the octane. Therefore you should reset your ECU periodically after filling up full tank in order to ensure that ECU adjustments for its octane memory are made afresh corresponding to the octane actually in use.
You can even customize resetting of your ECU so as to enable it to adapt itself to seasonal changes. Since humidity, air density, oxygen levels etc in air affect performance you could reset the ECU to adapt to these variables too.
The advantage of such resetting made to your ECU is that your car performs the best in every climatic condition. This lends versatility to your car- and all this at no cost.