The problem that we are dealing with is that Ford engineered these systems in such a way that IF some part DOES fail, the computer will keep the engine running "well enough" to still drive the vehicle but it will trigger the "Check Engine" light to warn the driver that even though the vehicle still APPEARS to be running properly, there is something amiss. Running this way for extended periods of time WILL eventually cause bigger problems unless its fixed. What folks who arbitrarily remove parts of the system FAIL to accept is the FACT that just because you remove or ignore the Check Engine light (or put tape over it...which is my personal favorite uneducated maneuver) does NOT mean the engine is "running fine" and further it means that whatever the EEC-IV computer is doing to compensate WILL cause other problems that WILL be worse in the long run. Remember the EEC-IV computer controls fuel-air ratio and spark timing along with shift points (E4OD only). Anyone who knows anything about internal combustion engines knows that these settings/adjustments are critical and failure to maintain them results in terrible problems if not immediately, then definitely over extended periods of time. When you are dealing with a vehicle where the ONLY way to be certain that these adjustments are correct is to make certain the on-board computer has ALL of the information it needs, maintaining ALL of the sources of that information becomes as critical as spark timing and fuel/air mixture. These are the FACTS.