Holley COMMANDER 950 - Manual (Page 28)

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Figure 9 Startup Enrichment Table
4. STARTUP / STARTS AND STALLS
If the engine starts and then stalls, it most likely needs more air and/or fuel. There are several areas that may need
tuning that relate to fuel.
For simplicity’s sake, at this time, we are going to stay in one area, the main fuel map. The other areas that will likely
need to be changed are the coolant temperature modifiers and the afterstart enrichment. If these areas are not ideal, we
will just tune the fuel map now to compensate. The idea is to allow the engine to stay running and get up to operating
temperature where the main fuel map can then be properly tuned. After the main fuel map is tuned with the engine up to
operating temperature, you will ONLY use the coolant temperature modifiers and the afterstart enrichment for cold engine
performance. Tuning these areas is covered in Required Additional EFI Tuning-Section 9.0.
Go to “Fuel” and “Main Fuel Map”. This brings up the main fuel map. The fuel map has 16 columns and rows. The
bottom indicates the engine rpm scale. The left column indicates manifold vacuum (or pressure). The bottom of the map
indicates high vacuum conditions. The top of the map indicates low vacuum that occurs at wide-open throttle conditions.
See Figure 11.
Start the engine. The area of the fuel map that the ECU is obtaining the fuel value from will be highlighted in red. The
following picture (Figure 10) shows an engine idling at 950 rpm with a manifold pressure of 43 kPa.
Figure 10 Example of Fuel Map with Engine Idling