Vane Airflow Sensor - Pinpoint Test DK Correction

89Ford09

Article No. 89-5A-5

EEC IV - 1.9L EFI AND 2.3L OHC TURBOCHARGED ENGINE - VANE AIRFLOW SENSOR - PINPOINT TEST "DK" - SHOP MANUAL CORRECTION

FORD: 1988 THUNDERBIRD, ESCORT

LINCOLN-MERCURY: 1988 COUGAR

MERKUR: 1988 XR4Ti

ISSUE: The Vane Airflow Sensor (VAF) sensor pinpoint test step DK2 on page 19-74 of the 1988 Engine Emissions Diagnosis Manual, Volume H, has been revised.

ACTION: If service is required, refer to Pinpoint Test "DK" on this TSB for revised diagnostic information. This information should be inserted into your 1988 Engine Emissions Diagnosis Manual, page 19-74.

OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: "INFORMATION ONLY"
OASIS CODES: 680000

1988
EEC-IV - Pinpoint Tests - All Vehicles 19-73

Vane Airflow Sensor

(VAF)

Pinpoint

Test

DK




[Note]

You should enter this Pinpoint Test only when a Service Code 26, 56, 66 or 76 is received in Quick Test Step 3.0, 5.0, or 6.0.


[Remember]

To prevent the replacement of good components, be aware that the following non-EEC areas may be at fault:

^ Check for unmetered air (air leaks) between VAF meter and throttle body.

^ Vacuum leaks.

^ Engine sealing (PCV sealing, CANP, valve cover seal dipstick seated).

This Pinpoint Test is intended to diagnose only the following:

^ VAF meter.

^ Processor.

^ Harness circuits: VREF, VAF SIGNAL and SIGNAL RETURN.


[Pinpoint Test Schematic]
19-74 1988 EEC-IV - Pinpoint Tests - All Vehicles



Vane Airflow Sensor

(VAF)
Pinpoint

Test
DK