Initial Tune Instructions

by Michael Decipha Ponthieux
Posted: 7-15-2013
Last updated: 9-4-2016

WARNING: NEVER return to an earlier tune during the tuning phase, doing so can result in engine damage and/or undesireable results.

These instructions are to be followed AFTER the Pre-Tuning Information is verified.

Before loading your custom EFIDynoTuning Tune, be sure to perform the following for best results.

ECU Memory Reset

It is very likely your ECU has saved KAM (keep-alive memory) data that it has learned from the previous or stock tune. These adaptive values save idle airmass correction and fuel correction data. It is highly recommended to clear the previously learned data so the ECU can adapt with new accurate information. The ECU's adaptive memory can be erased by disconnecting the battery for approximately 30 minutes NOTE: If your fuel pump runs constantly with your new tune installed, DO NOT TRY TO START THE ENGINE. The fuel pump running constantly is indicative that the tune being served to the ECU is corrupt. Attempting to start the vehicle with a corrupt tune can lead to excessive fueling and possibly engine damage.

Adjust Fuel Pressure Regulator to 55psi (< 60lb injectors)

If you do not have an adjustable fuel pressure regulator then skip this step. With an adjustable fuel pressure regulator, the base fuel pressure with the vacuum line disconnected should be set to either 55 psi for those with smaller than 60lb injectors or 40 psi for those with 60lb and larger injectors. Once the base fuel pressure has been set, the fuel pressure should DROP approx. 8 psi at idle when the vacuum line is reattached.

Verify base timing is 10*dBTDC

If you have an EDIS or DIS ignition system skip this step. It is VERY important that the base timing be set to 10 degrees BTDC, failure to do so can result in engine damage. Base timing can only be set with the SPOUT plug removed at a warm stabilized idle. Be sure the orientation of the distributor is mounted correctly as well, reference the Ignition Write Up for specifics. The orientation of the distributor is necessary for accurate injector timing. Aftermarket distributor's are less accurate and prone to failure. It is highly recommended to reinstall the stock factory distributor if you still have one available. If you have a boost reference ignition box, it is necessary to disable the boost retard function. The ECU will control timing based on boost. It is recommended to set the rev limiter on your ignition box to 6500-6600 rpm, unless discussed otherwise. Base timing must be set to 10dbtdc before base Idle can be adjusted in the next step. DO NOT PLUG THE SPOUT BACK IN UNTIL THE THROTTLE STOP IS SET CORRECTLY.

Base Idle Reset

In order for the ECU to control the IAC valve correctly, it has to be within' the pre-programmed range for idle airmass to be accurate. This can only be achieved ONCE THE ENGINE HAS REACHED A STABILIZED WARM IDLE by disconnecting the IAC valve connector, Throttle Position Sensor connector, and removing the SPOUT plug. To reach warm idle the engine must have already ran approx. 25 minutes idling from a cold startup. With the TPS, IAC, and SPOUT disconnected, adjust the throttle body stop screw until the engine idles at roughly 700-750. If the engine will not idle smooth at this low of an rpm, open the throttle stop screw until the engine idles stable. If the engine stalled as soon as you disconnected the IAC plug then you will need to turn the key off and put 2 complete turns on the throttle body stop to give the engine more air to idle. Temporarily plug in all the connectors again (IAC, TPS, SPOUT - needed for startup) and once the engine has reached a stabilized warm idle again (at least 3 minutes after warm startup) repeat the base idle reset to get it in the ballpark. Now that the base idle is set correctly and your engine is idling at 700-750 rpm, shut off the engine and reconnect the TPS, IAC, and SPOUT. Disregard the closed throttle TPS voltage value, as long as the closed throttle voltage is between 0.400 volts and 1.500 volts it is perfectly acceptable. The ECU uses the lowest voltage as a relative voltage of 0, so the voltage is irrelevant so long as its within' this range. Adjusting the TPS to get a closed throttle voltage of 0.99 volts is ignorant and will usually result in faulty idle control.

1st Drive to Fuel

It is highly recommended to take your vehicle to the gas station and fill up. Remember only use the highest grade PREMIUM fuel, unless otherwise discussed. Failure to use high octane fuel can result in engine damage. If you forget to fill up with high octane fuel, you do not need to drain your tank. Simply drive the vehicle like a normal human keeping the throttle below approx. 35% until your next fill up. REMEMBER, always FILL UP before going to the track or autocrossing, fuel slosh is real and can cause your engine to run lean. Always keep a full tank of fuel when racing your vehicle. The little bit of weight savings is not worth damaging your engine over. Also note, most aftermarket fuel pumps have a shorter operating life when not completely submerged in fuel. It is highly recommended to keep no less than a half tank at all times.


Continue on to Step 1 - First Time Startup - Idle Air
Continue on to Step 2 - Part Throttle Fuel and Spark
Continue on to Step 3 - WOT Fuel, Spark, and Load Scaling


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