Engine - Induction Backfire On Acceleration: Overview

Article No.
99-18-8

09/06/99

INDUCTION BACKFIRE - ON ACCELERATION - ALL
AMBIENT TEMPERATURES - VEHICLES WITH 4.2L
ENGINE - CANADIAN VEHICLES ONLY

FORD:
1997-1999 F-150

This TSB article is being republished in its entirety to include 1998 and 1999 model year vehicles.

ISSUE
Some vehicles may backfire on acceleration. This may occur at all ambient temperatures and may be caused by excessive Intake Valve Deposit (IVD). This may be due to carbon deposits on the intake valves.

ACTION
Perform diagnostics and clean intake valves if required. Refer to the following Service Procedure for details.

OTHER APPLICABLE ARTICLES: 93-12-6, 97-12-9

SUPERSEDES: 99-3-4

WARRANTY STATUS: Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage

OPERATION DESCRIPTION TIME

991808A Perform Intake Valve 0.5 Hr.
Deposit (IVD) Inspection

991808B Perform IVD Cleaning 2.8 Hrs.

991808C Extra Time To Reprogram 0.6 Hr.
Powertrain Control Module
(PCM) And Replace Spark
Plugs

DEALER CODING
CONDITION
BASIC PART NO. CODE
6507 49

OASIS CODES: 613000, 613500