Marquis L4-140 2.3L VIN A 1-bbl (1986)
Technical Service Bulletin # 8912A26
Date: 890627
Idle Fuel Mixture - Manual Revision
ENGINE EMISSIONS DIAGNOSIS SHOP MANUAL- 1986-SECTION 4-IDLE FUEL MIXTURE-PROPANE ENRICHMENT METHOD
ENGINE EMISSIONS DIAGNOSIS SHOP MANUAL- 1987-SECTION 4-IDLE FUEL MIXTURE-PROPANE ENRICHMENT METHOD
Article No. 89-12A-26
FORD:
1986 ESCORT, LTD, MUSTANG 1986-87 TEMPO 1986 THUNDERBIRD
LINCOLN-MERCURY: 1986 CAPRI, COUGAR, MARQUIS 1986-87 TOPAZ
LIGHT TRUCK:
1986 AEROSTAR 1986-87 BRONCO, ECONOLINE, F-150, F-250, F-350, RANGER
ISSUE:
The tachometer reference "or equivalent" as shown in procedure I.-B in both 1986 and 1987 Engine Emissions Diagnosis Manuals is
incorrect. This also applies to procedure I.-H in the 1986 Engine Emissions Diagnosis Manual.
ACTION:
Refer to the pages following this TSB article for the revised Volume H pages which show the correct tachometer designation as: "Connect
an analog tachometer, Rotunda 059-000010 or an equivalent analog tachometer." This information should be inserted in your 1986 Engine
Emissions Diagnosis Manual, pages 4-83, 4-87, 4-90, 4-93 and the 1987 Manual, pages 4-66 and 4-69.
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS:
INFORMATION ONLY
OASIS CODES:
680000
Pages 4-83, 4-84
1986
Carburetors, Fuel Charging Assemblies and Throttle Bodies
4-83
Idle Mixture Setting Procedures
IDLE FUEL MIXTURE-PROPANE ENRICHMENT METHOD
Passenger Car. 1.9L w/740-2V, 2.3L OHC w/YFA-IV FB, 2.3L HSC w/1949-IV, 3.8L w/2150-A-2V and 5.0L w/4180C-4V.
Truck, Under 8500 GVW: 5.8L w/4180C-4V.
NOTE:
This procedure is applicable to the above engines only. If CO and HC are not within specification, perform appropriate electrical diagnostic
procedure in Section 15.
I.
Vehicle Preparation: All Carburetors as noted above.
A.
Apply the parking brake, and block the wheels. Disconnect the automatic brake release, if so equipped, and plug the vacuum connection.
B.
Connect an analog tachometer, Rotunda 059-000010 or an equivalent analog tachometer.
C.
If so equipped, insure that the hot idle compensator is in a closed position and remains so throughout the test. Idle vehicle on kickdown step
of fast idle cam for three to five minutes to insure that HIC valve is closed.
D.
If so equipped, disconnect the fuel evaporative purge hose at the engine or the carburetor, (1.9L engines) and plug the connection. (Not
applicable to 5.0L and 5.8L Truck and 5.0L Passenger Car engines).
E.
If so equipped, disconnect the fuel evaporative purge hose at the air cleaner and plug the nipple. (Not applicable to 5.0L and 5.8L Truck and
5.0L Passenger car engines).
F.
Disconnect the flexible fresh air tube from the air cleaner duct or adaptor. Using propane enrichment Tool T75L-9600-A or equivalent, insert
the tool hose approximately 3/4 of the way into the duct or fresh air tube. If necessary, secure the hose with tape.
G.
For vehicles equipped with thermactor systems, revise the dump valve vacuum hoses as follows: (Not applicable to 1.9L engines).
1.
For dump valves with two vacuum fittings, disconnect and plug the hose(s).
