Chrysler PT Cruiser Service & Repair Manual page 271

PT
ENGINE - 2.0/2.4L DOHC (Continued)
CONDITION
TEMPERATURE GAUGE READING
IS INCONSISTENT (FLUCTUATES,
CYCLES OR IS ERRATIC)
POSSIBLE CAUSE
8. Freeze point of coolant not
correct. Mixture ratio may be too
rich.
9. Coolant not flowing through
system.
10. Radiator air seals missing or
improperly installed.
11. Radiator or A/C condenser fins
are dirty or clogged.
12. Radiator core is plugged or
corroded.
13. Fuel or ignition system
problems.
14. Dragging Brakes.
15. Bug screen or other aftermarket
accessory is being used causing
reduced air flow.
16. Thermostat partially or
completely closed.
17. Cooling fan not operating
properly.
18. Cylinder head gasket leaking.
19. Heater core leaking.
1. The gauge may cycle up and
down. This is due to the cycling of
the electric radiator fan.
2. During cold weather operation
with the heater blower in the high
position, the gauge reading may
drop slightly.
ENGINE - 2.0/2.4L DOHC
CORRECTION
8. Check coolant concentration
(Refer to 7 - COOLING/ENGINE/
COOLANT - DIAGNOSIS AND
TESTING). Adjust glycol-to-water
ratio as required.
9. Check for coolant flow at filler
neck with some coolant removed,
engine warm, and thermostat open.
Coolant should be observed flowing
through filler neck. If flow is not
observed, determine reason for lack
of flow and repair as necessary.
10. Inspect air seals. Correct as
necessary.
11. Clean obstruction from fins.
12. Replace or clean radiator.
13. Refer to the appropriate
Powertrain Diagnostic Procedure
manual.
14. Inspect brake system and repair
as necessary (Refer to 5 - BRAKES
- DIAGNOSIS AND TESTING).
15. Remove bug screen or
accessory.
16. Check thermostat operation and
replace as necessary (Refer to 7 -
COOLING/ENGINE/ENGINE
COOLANT THERMOSTAT -
DIAGNOSIS AND TESTING).
17. Check electric fan operation and
repair as necessary.
18. Check cylinder head gasket for
leaks (Refer to 7 - COOLING/
ENGINE - DIAGNOSIS AND
TESTING - COOLING SYSTEM
LEAK TESTING).
19. Check heater core for leaks.
1. A normal condition. No correction
is necessary. If gauge cycling is the
hot zone, check electric fan
operation and repair as necessary.
2. A normal condition. No correction
is necessary.
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