My thermostat

Tiny
J-BO
  • 2010 DODGE CHALLENGER
  • V8
  • 2WD
  • AUTOMATIC
  • 10,000 MILES

My check engine light keeps coming on and every time I take it to the mechanic they tell me it's because of the thermostat. I have a cold air intake in my 2010 Dodge Challenger, would that be the problem.

Do you
have the same problem?
Yes
No
Wednesday, February 16th, 2011 AT 8:15 PM

15 Replies

Tiny
WRENCHTECH
  • EXPERT
  • 20,907 POSTS

What is the exact code number being set?

Was this
answer
helpful?
Yes
No
Wednesday, February 16th, 2011 AT 8:52 PM
Tiny
J-BO
  • MEMBER

I don't know the code that's being set. The mechanics just keep telling me it's the thermostat

Was this
answer
helpful?
Yes
No
Wednesday, February 16th, 2011 AT 9:05 PM
Tiny
WRENCHTECH
  • EXPERT
  • 20,907 POSTS

So, have you changed the thermostat?

Was this
answer
helpful?
Yes
No
Wednesday, February 16th, 2011 AT 9:07 PM
Tiny
J-BO
  • MEMBER

Yes

Was this
answer
helpful?
Yes
No
Wednesday, February 16th, 2011 AT 9:14 PM
Tiny
J-BO
  • MEMBER

Yes I have

Was this
answer
helpful?
Yes
No
Wednesday, February 16th, 2011 AT 9:15 PM
Tiny
WRENCHTECH
  • EXPERT
  • 20,907 POSTS

Apparently his diagnosis was incorrect. We would need to code number to give you any adivice.

Was this
answer
helpful?
Yes
No
Wednesday, February 16th, 2011 AT 9:40 PM
Tiny
J-BO
  • MEMBER

Ok I'll get one for you

Was this
answer
helpful?
Yes
No
Wednesday, February 16th, 2011 AT 9:44 PM
Tiny
J-BO
  • MEMBER

I just checked it again. I had the code but I forgot. But the reader did say that the thermostat temperature was too cold. Could that be because of my cold air intake or my aftermarket exhaust?

Was this
answer
helpful?
Yes
No
Monday, February 28th, 2011 AT 12:42 AM
Tiny
WRENCHTECH
  • EXPERT
  • 20,907 POSTS

We still need an exact code number.

Was this
answer
helpful?
Yes
No
Monday, February 28th, 2011 AT 12:46 AM
Tiny
J-BO
  • MEMBER

I'm not sure but I think it said P118

Was this
answer
helpful?
Yes
No
Monday, February 28th, 2011 AT 12:53 AM
Tiny
WRENCHTECH
  • EXPERT
  • 20,907 POSTS

This is why we need the code number and not someone else's interpretation of what the code means. That code is for an electrical problem with the coolant temp sensor. It's reading too high meaning the signal is shorted somewhere in the circuit. It could be the sensor, the PCM or any related wiring.

Was this
answer
helpful?
Yes
No
Monday, February 28th, 2011 AT 12:58 AM
Tiny
J-BO
  • MEMBER

Ok. What do you recommend?

Was this
answer
helpful?
Yes
No
Monday, February 28th, 2011 AT 1:22 AM
Tiny
WRENCHTECH
  • EXPERT
  • 20,907 POSTS

Have it diagnosed properly.

Was this
answer
helpful?
Yes
No
Monday, February 28th, 2011 AT 1:26 AM
Tiny
J-BO
  • MEMBER

I took it in and got it diagnosed and the light came on again this time the code is P0128

Was this
answer
helpful?
Yes
No
Wednesday, March 23rd, 2011 AT 3:15 PM
Tiny
WRENCHTECH
  • EXPERT
  • 20,907 POSTS

P0128-THERMOSTAT RATIONALITY

For a complete wiring diagram, refer to the wiring information.

* When Monitored: With the engine running, start up coolant temperature between -8 C (17.6 F) and 50 C (122 F), the difference between ambient temperature and coolant temperature less than 10 C (50 F) and average vehicle speed greater than 16 kph (10 mph) for more than 18% of vehicle run time.
* Set Condition: The PCM detects that the actual engine coolant temperature does not reach the predicted engine coolant temperature within a specific time. Two trip fault. Three good trips to turn off the MIL.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. See: Initial Inspection and Diagnostic Overview Pre-Diagnostic Troubleshooting Procedure

1. CHECKING THE TEMPERATURE SENSORS.

NOTE: Diagnose and repair any ambient air temperature (AAT), intake air temperature (IAT), or engine coolant temperature (ECT) sensor circuit or rationality DTCs before continuing with this test.
NOTE: Diagnose and repair any crankshaft (CKP) or camshaft (CMP) sensor circuit or rationality DTCs before continuing with this test.
NOTE: Diagnose and repair any communication DTCs before continuing with this test.
NOTE: Verify that the Pinion Factor has been programmed correctly into the PCM.

1. Perform the diagnostic procedure for CHECKING THE TEMPERATURE SENSORS. See: Component Tests and General Diagnostics Checking the Temperature Sensors

Were any problems found?

Yes

* Repair as necessary.
* Perform the PCM VERIFICATION TEST. See: Verification Tests PCM Verification Test.

No

* Go To 2

2. CHECKING THE ENGINE COOLANT TEMPERATURE SENSOR OPERATION.

1. Perform the diagnostic procedure for CHECKING THE ENGINE COOLANT TEMPERATURE SENSOR OPERATION. See: Component Tests and General Diagnostics Checking the Engine Coolant Temperature Sensor Operation

Were any problems found?

Yes

* Repair as necessary.
* Perform the PCM VERIFICATION TEST. See: Verification Tests PCM Verification Test.

No

* Refer to the CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. See: Initial Inspection and Diagnostic Overview Checking for an Intermittent DTC

Was this
answer
helpful?
Yes
No
Wednesday, March 23rd, 2011 AT 3:21 PM

Please login or register to post a reply.

Recommended Guides