Diesel Engine - Idle Surge/Hard/No Start
89Ford28
ENGINE-6.9L AND 7.3L DIESEL-COLD IDLE TEMPERATURE SWITCH-DIAGNOSTIC TIPS
HARD START-6.9L AND 7.3L DIESEL-COLD IDLE TEMPERATURE SWITCH DIAGNOSTIC TIPS
NO START-6.9L AND 7.3L DIESEL-COLD IDLE TEMPERATURE SWITCH DIAGNOSTIC TIPS
SURGE-6.9L AND 7.3L DIESEL-COLD IDLE TEMPERATURE SWITCH DIAGNOSTIC TIPS
Article No. 89-18-9
LIGHT TRUCK: 1983-89 E-250, E-350, F-250, F-350
This article is being republished in its entirety to include hard start and no start conditions.
ISSUE: An RPM increase and/or engine surge, hard start or no start condition may be caused by a cold idle temperature switch that is not functioning properly. The switch is located on the top front of the right hand cylinder head.
ACTION: Use the following service procedure to diagnose and replace the cold idle temperature switch.
Figure 1:
1. Locate and disconnect the cold advance solenoid terminal connector at the left rear of the injector pump, Figure 1.
Figure 2:
2. Install a test lamp into the terminal connector and clamp to a suitable ground, Figure 2.
3. Turn the ignition switch key to the "IGN" position and proceed as follows:
COLD ENGINE (Temperature Below 85~F/29~C)
^ Check voltage at the cold advance solenoid terminal connector.
^ The test lamp should light, Figure 2.
^ If No voltage is present, replace the cold idle temperature switch.
HOT ENGINE (Temperature Above 123~F/52~C)
^ Check voltage at the cold advance solenoid terminal connector.
^ The test lamp should NOT light, Figure 2.
^ If voltage is present, replace the cold idle temperature switch.
PART NUMBER PART NAME CLASS
E8TZ-9E939-A Cold Idle Temperature Switch B
OTHER APPLICABLE ARTICLES: None
SUPERSEDES: 87-17-14, Date 8/26/87
WARRANTY STATUS: Eligible Under Basic Warranty Coverage
OPERATION DESCRIPTION TIME
891809A Diagnose & Replace Switch 0.4 Hr.
- F Series
891809B Diagnose & Replace Switch 0.5 Hr.
- Econoline
DEALER CODING
BASIC PART NO. CONDITION CODE
9E939 42
OASIS CODES: 610200, 610300, 630200, 620700, 4300