engine coolant DODGE RAM SRT-10 2006 Service Workshop Manual

Theory of Operation
The upstream O2 sensor is used to detect the amount of oxygen in the exhaust gas before the gas enters the
catalytic converter. During the catalyst/O2 monitor test, the response rate (cycles/second) of the upstream O2 sen-
sor determines the sensor’s ability to achieve the tailpipe emissions limits. The response rate of the downstream O2
sensor relative to the upstream O2 sensor response rate measures the catalyst’s ability to store oxygen and is used
to infer the catalyst’s ability to achieve the tailpipe emissions limits.
When Monitored:
After engine warm up to 147 deg. F, 180 seconds of open throttle operation, at a speed greater than 20 mph,
with the engine at 1200-1700 rpm and MAP vacuum between 15.0 and 21.0 inchesof mercury (Hg).
Set Condition:
As catalyst efficiency deteriorates, the switch rate of the downstream O2sensor approaches that of the
upstream O2 sensor. If at any point during the test the switch ratio reachesa predetermined value a counter
is incremented by one. Three good trips to turn off the MIL.
Possible Causes
EXHAUST LEAK
ENGINE MECHANICAL
AGING O2 SENSOR
CATALYTIC CONVERTER
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Diagnostic Test
1.ACTIVE DTC
NOTE: A new rear O2 Sensor along with an aging front O2 Sensor may cause the DTCtoset.Reviewthe
repair history of the vehicle before continuing.
NOTE: If an O2 Sensor DTC set along with the Catalytic Converter EfficiencyDTC diagnose the O2 Sensor
DTC(s) before continuing.
NOTE: Check for contaminants that may have damaged the O2 Sensor and Catalytic Converter: contami-
nated fuel, unapproved silicone, oil and coolant, repair necessary.
Ignition on, engine not running.
With a scan tool, read DTCs.
Is the DTC active at this time?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.VISUALLY INSPECT CATALYTIC CONVERTER
Inspect the Catalytic Converter for the following damage.
Damaged Catalytic Converter, dents or holes.
Severe discoloration caused by overheating the Catalytic Converter.
Catalytic Converter broken internally.
Leaking Catalytic Converter.
Were any problems found?
Ye s>>
Replace the Catalytic Converter. Repair the condition that may have caused the failure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 3

When Monitored:
Immediately after a cold start, with battery/ambient temperature between 40° F and 90° F and coolant tem-
perature within 10° F of battery/ambient.
Set Condition:
If there is a leak larger than 0.040
and smaller than 0.080in the evaporative system.
Possible Causes
EVAP PURGE SYSTEM LEAK
GAS CAP
EVAP PURGE SOLENOID
LEAK DETECTION PUMP
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Diagnostic Test
1.VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION
Ignition on, engine not running.
With a scan tool, read DTCs and record the related Freeze Frame data if any DTC(s) are present.
Whether or not any DTC(s) are present you will want to check the following items which may assist in repairing the
customer’s complaint successfully.
Check the vehicles repair history.
If the vehicle has a repair history that pertains to the customer’s currentcomplaint, review the repair.
Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly.
Check for any service bulletin(s) related to the customer’s complaint or DTC(s).
If a service bulletin applies, follow the instructions per the service bulletin.
Choose the following scenario that best applies.
The service bulletin repaired the customer’s complaint.
Testing complete.
A DTC is present, no service bulletins apply, or the service bulletin didn’t repair the customer’s complaint.
Go To 2
2.ACTIVE DTC
NOTE: Since a hot vehicle can conceal a leak, it is best to perform this test at room temperature.
NOTE: A loose gas cap could have caused this DTC to set. Make sure gas cap is tight and in good condi-
tion. Make sure the gas cap meets OEM specifications.
Ignition on, engine not running.
With a scan tool, read DTCs.
Is the DTC active at this time?
Ye s>>
Go To 3
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

When Monitored:
Immediately after a cold start, with battery/ambient temperature between 40° F and 90° F and coolant tem-
perature within 10° F of battery/ambient.
Set Condition:
If there is a leak larger than 0.080
in the evaporative system.
Possible Causes
EVAP PURGE SYSTEM LEAK
EVAP PURGE SOLENOID
LDP SWITCH
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
Diagnostic Test
1.VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION
Ignition on, engine not running.
With a scan tool, read DTCs and record the related Freeze Frame data if any DTC(s) are present.
Whether or not any DTC(s) are present you will want to check the following items which may assist in repairing the
customer’s complaint successfully.
Check the vehicles repair history.
If the vehicle has a repair history that pertains to the customer’s currentcomplaint, review the repair.
Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly.
Check for any service bulletin(s) related to the customer’s complaint or DTC(s).
If a service bulletin applies, follow the instructions per the service bulletin.
Choose the following scenario that best applies.
The service bulletin repaired the customer’s complaint.
Testing complete.
A DTC is present, no service bulletins apply, or the service bulletin didn’t repair the customer’s complaint.
Go To 2
2.ACTIVE DTC
NOTE: Since a hot vehicle can conceal a leak, it is best to perform this test at room temperature.
NOTE: A loose gas cap could have caused this DTC to set. Make sure gas cap is tight and in good condi-
tion. Make sure the gas cap meets OEM specifications.
Ignition on, engine not running.
With a scan tool, read DTCs.
Is the DTC active at this time?
Ye s>>
Go To 3
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

When Monitored:
With the engine running, coolant greater than 170°F, open throttle, steady to slightly increasing vehicle speed
greater than 18 mph but less than 55 mph, with a light load on the engine, for aperiod no less than 5 minutes.
Set Condition:
The oxygen sensor signal voltage is switching from below 0.39 of a volt to above 0.6 of a volt and back fewer
times than required.
Possible Causes
EXHAUST LEAK
RESISTANCE IN THE (K41) O2 SENSOR 1/1 SIGNAL CIRCUIT
RESISTANCE IN THE (K900) SENSOR GROUND CIRCUIT
O2 SENSOR
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.GOOD TRIP EQUAL TO ZERO
Ignition on, engine not running.
With the scan tool, read DTCs and record the related Freeze Frame data.
Is the Good Trip Counter displayed and equal to zero?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.EXHAUST LEAK
Start the engine.
Inspect the exhaust for leaks between the engine and the appropriate O2 Sensor.
Are there any exhaust leaks?
Ye s>>
Repair or replace the leaking exhaust parts as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 3
3.(K41) O2 SENSOR 1/1 SIGNAL CIRCUIT VOLTAGE DROP
Turn the ignition off.
Backprobe the (K41) O2 Sensor 1/1 Signal circuit at the 1/1 O2 Sensor harness connector and PCM harness con-
nector.
NOTE: Make sure the voltmeter leads are connected for positive polarity, meet the terminals in the connec-
tor, and that there is good terminal to wire connection.
NOTE: Make sure the voltmeter leads are connected for positive polarity
Start the engine.
Allow the engine to idle.
Is the voltage below 0.10 of a volt?
Ye s>>
Go To 4
No>>
Repair the excessive resistance on the (K41) O2 Sensor 1/1 Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

When Monitored:
With the engine running, coolant greater than 170°F, open throttle, steady to slightly increasing vehicle speed
greater than 18 mph but less than 55 mph, with a light load on the engine, for aperiod no less than 5 minutes.
Set Condition:
The oxygen sensor signal voltage is switching from below 0.39 of a volt to above 0.6 of a volt and back fewer
times than required.
Possible Causes
EXHAUST LEAK
RESISTANCE IN THE (K43) O2 SENSOR 2/1 SIGNAL CIRCUIT
RESISTANCE IN THE (K900) SENSOR GROUND CIRCUIT
O2 SENSOR
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.GOOD TRIP EQUAL TO ZERO
Ignition on, engine not running.
With the scan tool, read DTCs and record the related Freeze Frame data.
Is the Good Trip Counter displayed and equal to zero?
Ye s>>
Go To 2
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.EXHAUST LEAK
Start the engine.
Inspect the exhaust for leaks between the engine and the appropriate O2 Sensor.
Are there any exhaust leaks?
Ye s>>
Repair or replace the leaking exhaust parts as necessary.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
No>>
Go To 3
3.(K43) O2 SENSOR 2/1 SIGNAL CIRCUIT VOLTAGE DROP
Turn the ignition off.
Backprobe the (K43) O2 Sensor 2/1 Signal circuit at the 2/1 O2 Sensor harness connector and PCM harness con-
nector.
NOTE: Make sure the voltmeter leads are connected for positive polarity, meet the terminals in the connec-
tor, and that there is good terminal to wire connection.
NOTE: Make sure the voltmeter leads are connected for positive polarity
Start the engine.
Allow the engine to idle.
Is the voltage below 0.10 of a volt?
Ye s>>
Go To 4
No>>
Repair the excessive resistance on the (K43) O2 Sensor 2/1 Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

P1281-ENGINE IS COLD TOO LONG
For a complete wiring diagramRefer to Section 8W.
When Monitored:
The ignition key on, engine running.
Set Condition:
The engine does not warm to 176 Deg. F while driving for 20 minutes after start.
Possible Causes
ENGINE COLD TOO LONG
ECT SENSOR OPERATION
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
1.CHECK COOLING SYSTEM PERFORMANCE
NOTE: The best way to diagnose this DTC is to allow the vehicle to remain outside overnight in order to
have a completely cold soaked engine.
NOTE: Extremely cold outside ambient temperatures may cause this DTC to set.
Verify that the coolant level is not low and correct as necessary.
Start the engine.
With the scan tool, set the engine RPM to 1500 and allow the engine to warm up for 10-15 minutes.
With the scan tool, monitor the ENG COOLANT TMP DEG value during the warm up cycle. Make sure the transition
of temperature change is smooth.
Did the engine temperature reach a minimum of 80° C (176° F)?
Ye s>>
Go To 2
No>>
Refer to the Service Information for cooling system performance diagnosis. The most probable cause is
a Thermostat problem. Also, refer to any related TSBs.
Perform POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)
2.ECT SENSOR OPERATION
WARNING: WARNING: MAKE SURE THE ENGINE COOLING SYSTEM IS COOL BEFORE REMOVING THE
PRESSURE CAP OR ANY HOSE. SEVERE PERSONAL INJURY MAY RESULT FROM ESCAPING HOT COOL-
ANT. THE COOLING SYSTEM IS PRESSURIZED WHEN HOT.
With the scan tool, read and record the ECT Sensor Temperature value.
Using the DRB Temperature Probe #CH7050, measure the engine coolant temperature.
NOTE: The t-stat housing area should be around 192-195 at start to open.
Is the ECT Sensor value with -15°C (5°F) of the temperature probe reading?
Ye s>>
Te s t C o m p l e t e .
No>>
Replace the ECT Sensor.
Perform POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

When Monitored:
Immediately after a cold start, with battery/ambient temperature between 40 deg. F and 90 Deg. F and coolant
temperature within 10 Deg. F of battery/ambient.
Set Condition:
LDP test must pass first. If the PCM suspects a pinched hose it will not set a fault until it runs the EVAP purge
flow monitor. If the purge monitor does not pass then the pinched hose faultwill be set.
Possible Causes
EVAP CANISTER OBSTRUCTED
OBSTRUCTION IN HOSE/TUBE BETWEEN EVAP CANISTER AND PURGE SOLENOID
LDP PRESSURE HOSE OBSTRUCTED
LEAK DETECTION PUMP
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION
Ignition on, engine not running.
With a scan tool, read DTCs and record the related Freeze Frame data if any DTC(s) are present.
Whether or not any DTC(s) are present you will want to check the following items which may assist in repairing the
customer’s complaint successfully.
Check the vehicles repair history.
If the vehicle has a repair history that pertains to the customer’s currentcomplaint, review the repair.
Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly.
Check for any service bulletin(s) related to the customer’s complaint or DTC(s).
If a service bulletin applies, follow the instructions per the service bulletin.
Choose the following scenario that best applies.
The service bulletin repaired the customer’s complaint.
Testing complete.
A DTC is present, no service bulletins apply, or the service bulletin didn’t repair the customer’s complaint.
Go To 2
2.GOOD TRIP EQUAL TO ZERO
Ignition on, engine not running.
With the scan tool, read DTCs.
Is the Good Trip Counter displayed and equal to zero?
Ye s>>
Go To 3
No>>
Go To 8

When Monitored:
Immediately after a cold start, with battery/ambient temperature between 40 Deg. F and 90 Deg. F and coolant
temperature within 10 Deg. F of battery/ambient.
Set Condition:
The state of the switch does not change when the solenoid is energized.
Possible Causes
GOOD TRIP EQUAL TO ZERO
LDP VACUUM SUPPLY
LEAK DETECTION PUMP
(K107) LDP SWITCH SENSE CIRCUIT OPEN
(K107) LDP SWITCH SENSE CIRCUIT SHORTED TO GROUND
PCM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION
Ignition on, engine not running.
With a scan tool, read DTCs and record the related Freeze Frame data if any DTC(s) are present.
Whether or not any DTC(s) are present you will want to check the following items which may assist in repairing the
customer’s complaint successfully.
Check the vehicles repair history.
If the vehicle has a repair history that pertains to the customer’s currentcomplaint, review the repair.
Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly.
Check for any service bulletin(s) related to the customer’s complaint or DTC(s).
If a service bulletin applies, follow the instructions per the service bulletin.
Choose the following scenario that best applies.
The service bulletin repaired the customer’s complaint.
Testing complete.
A DTC is present, no service bulletins apply, or the service bulletin didn’t repair the customer’s complaint.
Go To 2
2.GOOD TRIP EQUAL TO ZERO
Check for any related TSBs.
Ignition on, engine not running.
With the scan tool, read DTCs and record the related Freeze Frame data.
Is the Good Trip Counter displayed and equal to zero?
Ye s>>
Go To 3
No>>
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

CONDITION POSSIBLE CAUSES CORRECTION
OIL PUMPING AT RINGS; SPARK
PLUGS FOULING1. Worn or damaged rings. 1. Hone cylinder bores and replace
rings.
2. Carbon in oil ring slots. 2. Replace rings (Refer to 9 -
ENGINE/ENGINE BLOCK/PISTON
RINGS - STANDARD
PROCEDURE).
3. Incorrect ring size installed. 3. Replace rings (Refer to 9 -
ENGINE/ENGINE BLOCK/PISTON
RINGS - STANDARD
PROCEDURE).
4. Worn valve guides. 4. Ream guides and replace valves
(Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE).
5. Leaking valve guide seals. 5. Replace valve guide seals.
DIAGNOSIS AND TESTING - CYLINDER COMPRESSION PRESSURE
The results of a cylinder compressionpressure test can be utilized to diagnose several engine malfunctions.
Ensurethebatteryiscompletelychargedandtheenginestartermotorisingood operating condition. Otherwise the
indicated compression pressures may not be valid for diagnosis purposes.
1. Clean the spark plug recesses with compressed air.
2. Remove the spark plugs.
3. Disable the fuel system (Refer to 14 - FUEL SYSTEM/FUEL DELIVERY - DESCRIPTION).
4. Remove the ASD relay (Refer to 8 - ELECTRICAL/IGNITION CONTROL/AUTO SHUTDOWNRELAY-
REMOVAL).
5. Insert a compression pressure gauge and rotate the engine with the engine starter motor for three revolutions.
6. Record the compression pressure on the 3rd revolution. Continue the test for the remaining cylinders.
7. (Refer to 9 - ENGINE - SPECIFICATIONS) for the correct engine compression pressures.
DIAGNOSIS AND TESTING - CYLINDERCOMBUSTION PRESSURE LEAKAGE
The combustion pressure leakage test provides an accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
Exhaust and intake valve leaks (improper seating).
Leaks between adjacent cylinders or into water jacket.
Any causes for combustion/compression pressure loss.
1. Check the coolant level and fill as required. DO NOT install the radiatorcap.
2. Start and operate the engine until it attains normal operating temperature, then turn the engine OFF.
3. Remove the spark plugs.
4. Remove the oil filler cap.
5. Remove the air cleaner hose.
6. Calibrate the tester according to the manufacturer’s instructions. The shop air source for testing should maintain
483 kPa (70 psi) minimum, 1,379 kPa (200 psi) maximum and 552 kPa (80 psi) recommended.
7. Perform the test procedures on each cylinder according to the tester manufacturer’s instructions. Set piston of
cylinder to be tested at TDC compression,While testing, listen for pressurized air escaping through the throttle
body, tailpipe and oil filler cap opening. Check for bubbles in the radiator coolant.
All gauge pressure indications should be equal, with no more than 25% leakage.
FOR EXAMPLE:At 552 kPa (80 psi) input pressure, a minimum of 414 kPa (60 psi) should be maintained in the
cylinder.

Refer to CYLINDER COMBUSTION PRESSURE LEAKAGE DIAGNOSIS CHART .
CYLINDER COMBUSTION PRESSURE LEAKAGE DIAGNOSIS CHART
CONDITION POSSIBLE CAUSE CORRECTION
AIR ESCAPES THROUGH
THROTTLE BODYIntake valve bent, burnt, or not
seated properlyInspect valve and valve seat.
Reface or replace, as necessary.
Inspect valve springs. Replace as
necessary.
AIR ESCAPES THROUGH
TAILPIPEExhaust valve bent, burnt, or not
seated properlyInspect valve and valve seat.
Reface or replace, as necessary.
Inspect valve springs. Replace as
necessary.
AIR ESCAPES THROUGH
RADIATORHead gasket leaking or cracked
cylinder head or blockRemove cylinder head and inspect.
Replace defective part
MORE THAN 50% LEAKAGE
FROM ADJACENT CYLINDERSHead gasket leaking or crack in
cylinder head or block between
adjacent cylindersRemove cylinder head and inspect.
Replace gasket, head, or block as
necessary
MORE THAN 25% LEAKAGE AND
AIR ESCAPES THROUGH OIL
FILLER CAP OPENING ONLYStuckorbrokenpistonrings;
cracked piston; worn rings and/or
cylinder wallInspect for broken rings or piston.
Measure ring gap and cylinder
diameter, taper and out-of-round.
Replace defective part as necessary
STANDARD PROCEDURE
STANDARD PROCEDURE - REPAIR DAMAGED OR WORN THREADS
CAUTION: Be sure that the tapped holes maintain the original center line.
Damaged or worn threads can be repaired. Essentially, this repair consistsof:
Drilling out worn or damaged threads.
Tapping the hole with a special Heli-Coil Tap, or equivalent.
Installing an insert into the tapped hole to bring the hole back to its original thread size.
STANDARD PROCEDURE - FORM-IN-PLACE GASKETS AND SEALERS
There are numerous places where form-in-place gaskets are used on the engine. Care must be taken when apply-
ing form-in-place gaskets to assure obtaining the desired results.Do not use form-in-place gasket material
unless specified.Bead size, continuity, and location are of great importance. Too thin a bead can result in leakage
while too much can result in spill-overwhich can break off and obstruct fluid feed lines. A continuous bead of the
proper width is essential to obtain a leak-free gasket.
There are numerous types of form-in-place gasket materials that are used in the engine area. Mopar
Engine RTV
GEN II, Mopar
ATF-RTV, and MoparGasket Maker gasket materials, each have different properties and can not
be used in place of the other.
MOPAR
ENGINE RTV GEN II
Mopar
Engine RTV GEN II is used to seal components exposed to engine oil. This material is a specially designed
black silicone rubber RTV that retains adhesion and sealing properties when exposed to engine oil. Moisture in the
air causes the material to cure. This material is available in three ounce tubes and has a shelf life of one year. After
one year this material will not properly cure. Always inspect the package for the expiration date before use.
MOPAR
AT F R T V
Mopar
ATF RTV is a specifically designed black silicone rubber RTV that retains adhesion and sealing properties
to seal components exposed to automatic transmission fluid, engine coolants, and moisture. This material is avail-
able in three ounce tubes and has a shelf life of one year. After one year thismaterial will not properly cure. Always
inspect the package for the expiration date before use.
MOPAR
GASKET MAKER