Po126 code

[HowieE]

Can you tell what a PO126 code relate to? I can not find this code in my manuals. The code is coming from a 1998 K2500.

[diesel65]

Hi Howie,
P0126 is a code for "Engine coolant temperature insufficient for stable operation"
What the computer is telling you is the engine did not reach a minimum temperature in a certain time frame.
What I have found it one of the thermostats is stuck open partially.

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