Sable lunges and speeds out of control

Mercury Sable 2002 When i stop at a traffic light and with my foot on the brake peddle, the car will lunge forward 3 to 4 feet and the engine will rev. On the open road the car will begin to gain speed and the check brake and traction contol idiot lights come on.(The gas peddle is not stuck or appears to have any problems according to the pros.) I must to turn off the engine to stop the acceleration. The idiot lights stay on for an hour or two and go off in the driveway at the dealership. Two shops and two dealerships have been unable to find the source of the problem. Scary!!! This happens about every 3 to 5 months. Any ideas?
thanks
jim

If the lights came on it should have set codes. Did they pull any codes? Has it happened lately? Could you have the codes pulled at the local parts store. There is a service bulletin for surge on correct installation of the CMP sensor.
Article No.
02-22-1

11/11/02

^ DRIVEABILITY - SURGE/ROLLING IDLE - GEAR
DRIVEN SYNCHRONIZERS - INCORRECT
INSTALLATION - CAMSHAFT POSITION
SYNCHRONIZER (CMP) INSTALLATION TOOL
CORRECT APPLICATION

^ ENGINE - GEAR DRIVEN SYNCHRONIZERS -
INCORRECT INSTALLATION - CAMSHAFT POSITION
SYNCHRONIZER (CMP) INSTALLATION TOOL
CORRECT APPLICATION

MERCURY:
1994-1997 COUGAR
1995-2003 SABLE
1997-2000 MOUNTAINEER

ISSUE

Incorrectly installed gear driven camshaft position (CMP) sensor synchronizer assemblies may be hard to diagnose. Vehicle may exhibit poor fuel economy, driveability Diagnostic Trouble Codes (DTCs) P1336, P1309, P0340 with MIL light on. Loss of power, surge, hesitation and runs rough on acceleration may also be present.

ACTION

New diagnostics have been developed for WDS to diagnose incorrectly installed gear driven camshaft position (CMP) synchronizer assemblies. Refer to the following Service Procedure to diagnose a possible mis-installed synchronizer assembly and proper installation procedure

Thank you…
the dealer and shop said there were no codes pulled.