Engine Rpm/Vehicle Speed Limiter
WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2003 Mercury Sable, 2003 Mercury Mountaineer, 2003 Mercury Marauder, 2003 Mercury Grand Marquis, and 2003 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.
The Powertrain Control Module (PCM) will disable some or all fuel injectors whenever an engine RPM or vehicle overspeed condition is detected. The purpose of engine RPM/vehicle speed limiter is to prevent damage to vehicle powertrain. Vehicle will run rough, and PCM will store a continuous memory DTC P1270. When overspeed condition is over, engine will return to normal operation. If necessary, clear DTC P1270 from PCM.