Speed Control; Description; Diagnosis And Testing - Road Test; Specifications - Dodge RAM 1500 1998 Owner's Manual

DR
SPEED CONTROL (Continued)
(5) Verify operation of one-way check valve and
check it for leaks.
(a) Locate one-way check valve. The valve is
located in vacuum line between vacuum reservoir
and engine vacuum source. Disconnect vacuum
hoses (lines) at each end of valve.
(b) Connect a hand-operated vacuum pump to
reservoir end of check valve. Apply vacuum. Vac-
uum should not bleed off. If vacuum is being lost,
replace one-way check valve.
(c) Connect a hand-operated vacuum pump to
vacuum source end of check valve. Apply vacuum.
Vacuum should flow through valve. If vacuum is
not flowing, replace one-way check valve. Seal the
fitting at opposite end of valve with a finger and
apply vacuum. If vacuum will not hold, diaphragm
within check valve has ruptured. Replace valve.
5.7 Gas
Vacuum is not used for any part of the speed con-
trol system if equipped with a 5.7L V-8 engine.
5.9L Diesel Engine With Manual Trans.
Vacuum is not used for any part of the speed con-
trol system if equipped with a diesel engine and a
manual transmission.
5.9L Diesel Engines With Automatic Trans.
If equipped with a diesel powered engine and an
automatic transmission, an electric vacuum pump
and vacuum lines are used to supply vacuum to the
speed control servo. A vacuum reservoir is not used.

DIAGNOSIS AND TESTING - ROAD TEST

Perform a vehicle road test to verify reports of
speed control system malfunction. The road test
should include attention to the speedometer. Speed-

SPECIFICATIONS

TORQUE - SPEED CONTROL

DESCRIPTION

Servo Mounting Bracket-
to-Servo Nuts
Servo Mounting Bracket-
to-Battery Tray Screws
Speed Control Switch
Mounting Screws
Vacuum Reservoir
Mounting Nuts
ometer operation should be smooth and without flut-
ter at all speeds.
Flutter in the speedometer indicates a problem
which might cause surging in the speed control sys-
tem. The cause of any speedometer problems should
be corrected before proceeding. Refer to Instrument
Cluster for speedometer diagnosis.
If a road test verifies a system problem and the
speedometer operates properly, check for:
• A Diagnostic Trouble Code (DTC). If a DTC
exists, conduct tests per the Powertrain Diagnostic
Procedures service manual.
• A misadjusted brake (stop) lamp switch. This
could also cause an intermittent problem.
• Loose, damaged or corroded electrical connec-
tions at the servo (if used). Corrosion should be
removed from electrical terminals and a light coating
of Mopar
applied.
• Leaking vacuum reservoir (if used).
• Loose or leaking vacuum hoses or connections (if
used).
• Defective one-way vacuum check valve (if used).
• Secure attachment of both ends of the speed con-
trol servo cable (if used).
• Smooth operation of throttle linkage (if used)
and throttle body air valve.
• Failed speed control servo (if used). Do the servo
vacuum test.
CAUTION: When test probing for voltage or conti-
nuity at electrical connectors, care must be taken
not to damage connector, terminals or seals. If
these components are damaged, intermittent or
complete system failure may occur.
N-m
7
4
1.7
3

SPEED CONTROL

MultiPurpose Grease,
Ft. Lbs.
-
-
-
-
8P - 3
or equivalent,
In. Lbs.
60
30
15
20