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Discussion Starter · #1 ·
Hey I have tried looking on here, looking on google and everywhere that I could look been looking for the past 2 hours since i got home from the meet, and I am lost. I know what the code is. but that is it nothing more.

P0961 : Line pressure control Sol, system performance

How can I go about finding out what I have to do to fix this, and what I have to do to go about trouble shooting this. I have a really hard 1-2 shift. Not always but 80% of the time. I pulled up some info on what sort of sounded like mine, with some same problems, but not like mine. and not about the 355 platform. Right now I think this is really hurting my gas econ. I get just under 300 to a full tank on a 2.9L. Any and all help would be great. Thank you
 

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Discussion Starter · #3 ·
So no one has any idea or clue on this? Any help or info would help out. I really need to try to get my truck fixed, my gas econ is low as hell, and the hard 1-2 shifts are getting to be annoying. and not so good in the rain with the family in the car.
 

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Circuit Description
The pressure control (PC) solenoid valve is an electronic device that regulates transmission line pressure based on the current flow through its coil winding. The magnetic field produced by the coil moves the solenoid's internal valve which varies pressure to the pressure regulator valve. The transmission control module (TCM) controls the PC solenoid valve by applying a varying amount of amperage to the solenoid. The applied amperage can vary from 0.1-1.1 amps. Low amperage, 0.1 amp, indicates high line pressure. High amperage, 1.1 amps, indicates low line pressure. The duty cycle of the PC solenoid valve is expressed as a percentage of energized ON time. Zero percent indicates zero ON time, non-energized, or no current flow. Approximately 60 percent at idle indicates maximum ON time, energized, or high current flow. The TCM determines the appropriate line pressure for a given load by comparing the throttle position sensor voltage, the engine speed and other inputs.

When the TCM detects a continuous open or short to ground in the PC solenoid valve circuit, then DTC P0961 sets. DTC P0961 is a type C DTC.

DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0961 Line Pressure Control (PC) Solenoid System Performance

Conditions for Running the DTC
•The system voltage is 8-18 volts.
•The engine is running.

Conditions for Setting the DTC
The PC solenoid valve duty cycle reaches its high limit, approximately 95 percent, or low limit, approximately 2 percent.

Action Taken When the DTC Sets
•The TCM does not request the engine control module (ECM) to illuminate the malfunction indicator lamp (MIL).
•The TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM records this information as a Failure Record.
•The TCM commands maximum line pressure.
•The TCM freezes transmission adaptive functions.
•The TCM stores DTC P0961 in TCM history.

Conditions for Clearing the DTC
•The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring.
•A scan tool can clear the DTC.

Diagnostic Aids
DTC P0961 may set under low voltage conditions caused by high electrical system demands.
 
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