Pickup 4WD L4-144.4 2366cc 2.4L SOHC (22R-E) (1986)
Carburetor: All Technical Service Bulletins
Fuel - Hesitation When Accelerating From A Stop
REFERENCE ENGINE NUMBER 008 DATE 11-8-85
MODEL RN
CONDITION:
Some 1985 carbureted, federal emissions specification trucks may exhibit a slight hesitation when accelerating from a stop, or during light throttle
acceleration at low speeds.
CAUSE:
This condition may be caused by:
(1)
Lean air fuel mixture.
(2)
EGR influence on lean mixture.
CORRECTION:
(1)
Operating temperature of the EGR valve BVSV has been changed from 40~C to
60~C.
(2)
Diameter of the slow jet has increased from 0.50mm to 0.52mm.
(3)
Diameter of the main jet has increased from 1.14mm to 1.17mm (ATM) or 1.16mm (MTM).
(4)
On high altitude specification vehicles, the carburetor air horn has also been changed to allow installation of the new jets.
PRODUCTION EFFECTIVE:
From Engine Number
Production Date
22R-1590303
September, 1985
PART NUMBER INFORMATION:
The following part numbers have changed in production as of September 1985.
Previous Part Number
New Part Number
Part Name
21100-35290
21100-35291
Carburetor Assy (MTM)
21100-35301
21100-35302
Carburetor Assy (ATM)
25820-13010
25820-13020
Valve Assy Bimetal
SERVICE REPLACEMENT PART NUMBER INFORMATION:
To correct a hesitation condition on vehicles produced prior to September 1985 the following parts must be replaced as a set.
Part Number
Part Name
21205-35210
Jet, sub assy, slow (ATM & MTM)
90999-41116
Jet, first main (MTM)
90999-41117
Jet, first main (ATM)
25820-13020
Valve assy bimetal, (ATM & MTM)
On high altitude specification vehicles the air horn must also be replaced.
Part Number
Part Name
21112-35291
Horn, air (MTM, high altitude)
21112-35300
Horn, air (ATM, high altitude)