Idle Speed Setting Procedure - Manual Revision

89Ford19

ENGINE EMISSIONS DIAGNOSIS SHOP MANUAL-1989-

SECTION 4-IDLE SPEED SETTING PROCEDURES REVISED

Article No. 89-12A-24

FORD: 1989 TAURUS

LIGHT TRUCK: 1989 RANGER


ISSUE: The Idle Speed Setting Procedures on page 4-16, 4-19, 4-20, and 4-21 of the 1989 Engine Emissions Diagnosis Manual are incorrect.

ACTION: Refer to the pages following this TSB article for the revised procedures. This information should be inserted in your 1989 Engine Emissions Diagnosis Manual, pages 4-16, 4-19, 4-20, and 4-21.

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




Carburetors, Throttle Bodies and Injectors 1989 4-15


CFI, EFI & Carburetor System Troubleshooting


1989
4-16 Carburetors, Throttle Bodies and Injectors


Idle Speed Setting Procedure


[Note]


The curb idle and fast idle speeds are controlled by the EEC-IV processor and the idle speed control device and cannot be adjusted.


[Remember]

A change in idle speed occurred because of a problem elsewhere. You should only enter this procedure after you have eliminated the possible causes listed below:

^ Contamination within the throttle bore

^ Contamination within the idle speed control device

^ Throttle sticking or binding

^ Engine not reaching operating temperature

^ Vacuum leaks (air intake manifold, vacuum hoses, vacuum reservoirs, power brake booster where applicable, etc.)


[Verify]

^ Transmission in PARK or NEUTRAL

^ Parking brakes applied (automatic brake release disconnected where applicable)

^ Wheels blocked

^ Cooling system filled

^ Engine at operating temperature

^ Heater and accessories off

^ Throttle lever is resting on the throttle plate stop screw (EFI only)

^ Ignition timing set to specification

a. Perform EEC-IV diagnostics and resolve any vehicle malfunction that are indicated by service output codes. (Ignore this step if you were sent here from an EEC-IV Pinpoint Test Step).

b. Engine off, disconnect the negative ( - ) terminal of the battery for five minutes minimum then reconnect it. (Omit this step if you are required to do it in Step 8 for Truck).

c. Start engine and stabilize for two minutes, then goose engine and let it return to idle, lightly depress and release the accelerator and let engine idle. Does engine idle properly?

NOTE: If electric cooling fan comes on, wait until it turns off.

d. If engine does not idle properly, SHUT ENGINE OFF. Go to the appropriate adjustment procedure page. Follow the procedure from top of the page in sequence to the bottom of the page.




1989
Carburetors, Throttle Bodies and Injectors 4-19


Idle Speed Setting Procedures





4-20 1989 Carburetors, Throttle Bodies and Injectors


Idle Speed Setting Procedures


NOTE: For Step 6, if you must turn the throttle stop screw in, shut engine off, make estimated adjustment. Start engine and repeat Steps 4, 5, and 6 before continuing. 3 4.9L Calibrations: 7-52ER-, 7-52JR-, 7-52KR-, 7-52MR-, 7-52QR-, 7-52RR-, 7-52ZR-, 7-72JR-. 4 All other 4.9L Calibrations.

NOTE: For Step 12, a condition may occur where the engine rpm will oscillate. This can be caused by the throttle plates being open enough to allow purge flow. To verify this condition, disconnect the carbon canister purge line and plug it. If purge is present, the throttle plates must be closed until the purge flow induced idle oscillations stop.




Carburetors, Throttle Bodies and Injectors 1989 4-21


Idle Speed Setting Procedures




4-22 1989 Carburetors, Throttle Bodies and Injectors


Idle Speed Setting Procedures