Explorer 2WD V6-245 4.0L SOHC VIN E EFI (1997)
PROM - Programmable Read Only Memory: Customer Interest
Exhaust - Booming Noise 700-800 RPM On Cold Startups
Article No.
98-1-18
01/19/98
NOISE - "BOOMING" NOISE AT 700-800 RPMS
DURING COLD START - 4.0L SOHC VEHICLES
LIGHT TRUCK:
1997-98 EXPLORER
CALIBRATION:
7-58C-R11, 7-58V-R11, 8-58C-R05, 8-58V-R05
WARNING:
THIS MODIFICATION IS AUTHORIZED ONLY FOR THE LISTED ENGINE. PERFORMING THIS MODIFICATION ON OTHER ENGINE
CALIBRATIONS IS UNAUTHORIZED AND COULD CREATE LIABILITY UNDER APPLICABLE FEDERAL OR LOCAL LAWS.
This TSB lists the latest level calibrations, all past revision levels are also included.
ISSUE:
An audible "booming" noise may be heard at an idle with engine speeds between 700-800 rpms on cold startups on some vehicles. This may be caused
by a resonance within the exhaust system.
ACTION:
Reprogram the Powertrain Control Module (PCM). The revised calibration will limit the amount of time the vehicle's rpm stays in the critical range
which is causing the noise. Refer to the Recalibration Cross Reference Chart for the correct PCM calibration.
Perform all normal diagnostics as outlined in the appropriate Explorer Workshop Manual.
Obtain an Authorized Modification Decal (FPS 8262 - obtainable through DOES II, 25/pkg) and list the date, dealer number, and summary of
modifications performed. Select a prominent place adjacent to the Vehicle Emission Control Information Decal suitable for installing the Authorized
Modifications Decal. Clean the area, install the decal, and cover it with a clear plastic decal shield.
NOTE:
PCM REPLACEMENT IS NOT AUTHORIZED BY THIS TSB. REFER TO THE POWERTRAIN CONTROL/EMISSIONS DIAGNOSIS
(PC/ED) SERVICE MANUAL FOR APPROPRIATE DIAGNOSTIC PROCEDURES IF PCM HARDWARE CONCERNS EXIST.
OTHER APPLICABLE ARTICLES: 97-7-6
