| I won’t get into the wisdom of changing chips while the ECU is powered-up, but changing chips while the computer is powering-down is a definite no-no.
The 1.6M ECU (used in a 748) has an internal power supply that keeps it powered-up for 15 seconds after you turn the key off. It uses this time to do some internal housekeeping. If you pull the EPROM during this period, the computer isn’t EVER able to re-boot properly. This can also damage the coil drivers.
So, pull the wiring harness quick-disconnect off the ECU, and wait a bit before pulling the chip.
[Edited on 12-20-2004 by Shazaam!] |