Engine - Hard Starting/Long Cranking Time
90ford47 Article No. 90-26-11HARD STARTING - 7.3L DIESEL ENGINE - LONG CRANKING TIME
LIGHT TRUCK: 1988-90 E-250, E-350, F SUPER DUTY, F-250, F-350
This TSB article is being republished in its entirety to correct the procedure listed in method # 2. The ignition must be in the "ON" position.
ISSUE: Hard starting and long cranking time of more than five (5) seconds may occur if the "WAIT TO START" light turns off too early. This may be caused by the strategy of the electronic glow plug control module or by the resistor bar on the electronic glow plug control module.
ACTION: Install a resistor bar kit (E9TZ-12B602-A) on the electronic glow plug control module or replace the glow plug control module (FOTZ-12B533-A). Refer to the following procedure for service details.
Figure 1:
32 DEGREES F AND BELOW
For trucks built before 11/89 only, install a resistor bar kit (E9TZ-12B602-A) on the electronic glow plug control module, Figure 1.
NOTE: TRUCKS BUILT FROM 11/89 THROUGH THE END OF THE 1990 MODEL YEAR ALREADY HAVE THIS RESISTOR BAR INSTALLED.
This resistor bar kit causes an increase in the glow plug temperature before the "WAIT TO START" light turning off.
32 DEGREES F AND ABOVE
For trucks built before the 1991 model year, replace the electronic glow plug control module (FOTZ-12B533-A), Figure 1. This module is located behind the Crankcase Depression Regulator held on with two (2) bolts.
NOTE: THE 1991 MODELS ALREADY HAVE THIS MODULE INSTALLED.
This module increases the "ON" time of the "WAIT TO START" light.
ALTERNATIVE ACTION TO INSTALLING ELECTRONIC GLOW PLUG CONTROL MODULE
An alternative action to installing the module is described below. This alternative requires a modification to the starting instructions outlined in the Owner's Guide, 7.3L Diesel Supplement.
32 DEGREES F AND ABOVE
For trucks built before 11/89, install the resistor bar kit (E9TZ-12B602-A).
For all affected 1988-90 trucks, disregard the "WAIT TO START" on the dash and use any of the following methods during starting.
Method # 1
^ Insert key
^ Turn the dome light on.
^ Turn key to the "ON" position. (The dome lamp will visibly dim.)
^ When the dome lamp brightens again, depress the accelerator pedal and engage the starter as specified in the Owner's Guide.
^ Turn the dome lamp off.
Method # 2
^ Insert key.
^ Turn off the radio, fan, and other sound generating accessories.
^ Turn the ignition key to the "OFF" position.
^ Wait until the intermittent "clicking" of the glow plug control module is heard.
^ Depress the accelerator pedal and engage the starter as specified in the Owner's Guide.
Method # 3
^ Insert key.
^ Turn the ignition key to the "ON" position.
^ Wait until the 'WAIT TO START" light goes off.
^ Count to five.
^ Depress the accelerator pedal and engage the starter as specified in the Owner's Guide.
NOTE: INSTALLATION OF THE GLOW PLUG MODULE (FOTZ-12B533-A) WILL NOT DECREASE CRANK TIME BELOW THAT ACHIEVED BY ANY OF THE THREE METHODS JUST DESCRIBED.
The resistor bar kit and the electronic glow plug control module cause the "WAIT TO START" light to remain "on" for a longer time. Installing them will allow the customer to follow the starting instructions outlined in the Owner's Guide, 7.3L Diesel Supplement and bring the starting time to a more acceptable level.
If the hard starting condition continues, perform the following checks to rule out other possible causes of excessive cranking time. Refor to the 1988/90 Engine/Emissions Diagnosis Manual, Section 20, for service details.
OTHER ITEMS TO CHECK
^ Make sure that the battery voltage is a minimum of 12.5 volts. (Reading taken at either battery.)
^ Check the voltage supply from the glow plug control module to the glow plug system. The minimum value should be 7 volts. If there is less than 7 volts, check the fusible link and/or service wiring.
^ Make a resistance check on all the glow plugs (0.4 - 0.6 ohms). If they are not within specification, replace them as required.
^ Make sure that only good quality fuel is used.
^ Make sure that there are no fuel system suction side air leaks.
PART NUMBER PART NAME CLASS
E9TZ-12B602-A Resistor Bar Kit B
FOTZ-12B533-A Electronic Glow Plug Control B
Module
OTHER APPLICABLE ARTICLES: 88-9-13
SUPERSEDES: 90-24-11
WARRANTY STATUS: Eligible Under Basic Warranty Coverage
OPERATION DESCRIPTION TIME
902611A Diagnose & Install Resistor 0.9 Hr.
- E Series
902611A Diagnose & Install Resistor 0.8 Hr.
- F Series
902611B Diagnose & Install Module - 1.0 Hr.
E Series
902611B Diagnose & Install Module - 0.9 Hr.
F Series
DEALER CODING
BASIC PART NO. CONDITION CODE
12B602 53
OASIS CODES: 602300