My 2003 Saturn vue just bought it used.Fixed lots of normal things Already. but check engine light stays on.security light on when cuts off.Driving.change oil soon. Already done.confused.worried

Jeffrey Turcotte

• 8991 Answers
• Posted on Jul 02, 2011

SOURCE: I have 3 questionable codes.

Hi, the codes 1791 and 2138 indicate the accelerator position sensor. The code 700 is a generic transmission control system error, with may be caused by the error in accelerator position data. Your car has redundant sensors on the accelerator pedal, which explains why the car is still operating OK. I recommend you test the sensors to verify the problem. If the sensors test good, the problem may be a bad connection or a broken wire. I have pasted testing and replacement instructions below. If you have the 3.0 liter engine, the wire colors are the same as the 3.5 liter engine. I you don't have a scanner, skip to the tests using a multimeter. If you have no test equipment, you may want to borrow a multimeter. A new sensor costs over $100. Please let me know if you have any questions, and thanks for using FixYa.


OperationThe accelerator pedal contains 2 individual Accelerator Pedal Position (APP) sensors within the assembly. The APP sensors 1 and 2 are potentiometer type sensors each with 3 circuits:

A 5-volt reference circuit A low reference circuit A signal circuit


The APP sensors are used to determine the pedal angle. The Powertrain Control Module (PCM) provides each APP sensor with a 5-volt reference circuit and a low reference circuit. The APP sensors provide the PCM with signal voltage proportional to the pedal movement. The APP sensor 1 signal voltage at rest position is near the low reference and increases as the pedal is actuated. The APP sensor 2 signal voltage at rest position is near the 5-volt reference and decreases as the pedal is actuated.

Testing

1. Before beginning vehicle diagnosis, the following preliminary inspections/tests must be performed:
   
   Ensure that the battery is fully charged Ensure that the battery cables are clean and tight Inspect for any open fuses Ensure that the grounds are clean, tight, and in the correct location Inspect the easily accessible systems or the visible system components for obvious damage or conditions that could cause the concern. This would include checking to ensure that all connections/connectors are fully seated and secured Inspect for aftermarket devices that could affect the operation of the system Search for applicable service bulletins
   
2. Install a scan tool. Verify that the scan tool powers up.
3. With the ignition ON, engine OFF, verify communication with all of the control modules on the vehicle.
4. With the ignition ON, observe the scan tool APP sensor 1 voltage parameter. The readings should be 1.0 volt at rest to just above 4.0 volts when fully depressed. Ensure there is a voltage change with accelerator pedal movement.
5. With the ignition ON, observe the scan tool APP sensor 2 voltage parameter. The readings should be 0.5 volts at rest to more than 2.0 volts with the accelerator pedal fully depressed. Ensure there is a voltage change with accelerator pedal movement.
6. Connect a fused jumper wire between the APP sensor 2 5-volt reference circuit and the APP sensor 2 signal circuit at the accelerator pedal harness connector.
7. Observe the APP sensor 2 voltage parameter with a scan tool. It should read 4.6-5.2 volts.
8. Turn OFF the ignition. Remove the fused jumper.
9. Turn ON the ignition, with the engine OFF.
10. Measure the voltage of the APP sensor 5-volt reference circuit with a DMM. It should read 4.6-5.2 volts.
11. If the reference voltage is below the acceptable range, check the low reference circuit for an open or high resistance interruption.
12. If all circuits are functioning properly and there is no voltage change when the accelerator pedal is moved, replace the APP.

Fig. Accelerator Pedal Position (APP) connector end view-2.2L engine

Removal & Installation

1. Before servicing the vehicle, refer to the Precautions Section.
2. Disconnect the Connector Position Assurance (CPA) from the Accelerator Pedal Position (APP) sensor connector.
3. Disconnect the APP sensor harness connector.
   NOTE Due to clearance issues, the upper attachment bolt cannot be removed from the accelerator pedal assembly. Loosen the bolt completely and leave the bolt in the component until the assembly is removed from the vehicle.
   
   NOTE A speed wrench may be used to aid in the removal and installation.
   
4. Remove the APP assembly attachment bolts to the brake pedal assembly.
5. Remove the APP assembly from the vehicle.

1. Install the upper attachment bolt into the APP assembly.
2. Install the APP assembly into the vehicle.
3. Install the attachment bolts into the APP assembly. Tighten the accelerator pedal position assembly-to-brake bracket bolt to 18 ft. lbs. (25 Nm).
4. Connect the APP sensor harness connector. Push the connector in until the lock position is felt, then pull back to confirm engagement.
5. Install the APP sensor and connect the CPA.

Marvin

• 85242 Answers
• Posted on Feb 12, 2009

SOURCE: service engine soon light on 2003 Saturn Vue

Here is the definition of the code in GM manual:
P0128 - Coolant Thermostat Below Thermostat Regulating Temperature, this indicates the engine is running cold, u need a thermostat

SOURCE: 2004 Saturn VUE (M/T) STEADY service engine soon light

SOME TIME PCM GET A VOLTAGE SPIKE.OR ELECTRICAL INTERFERENCE WILL CAUSE SERVICE LIGHT TO COME ON WITH NO CODES.IF IT KEEP HAPPENING TAKE IT TO DEALERSHIP TO CHECK IT OUT.

SOURCE: 2003 saturn vue. replaced spark plugs and the

Did you use the recommended plugs or did you use a new style like E-3 or Bosch +4 or something similar. Sometimes using a plug other than the original type can cause problems. Check and make sure all the wires or plug connections to the plugs are secure. Check to see if a spark plug has a cracked insulator. If you used antiseize on the threads make sure none of it got on the spark plug electrode or it will missfire.

Hope these ideas help.

Bob

SOURCE: what does po440 on a 2003 saturn vue mean with a

That is a problem in the evaporative emission control system.
Could be anything causing it
Clogged filter in the charcoal canister
A leak in one of the vacuum lines
The purge valve not working,,,etc.
The best thing is to take it and have it checked out, they might have to do a smoke test to find the problem.
All they do is inject smoke into the system, if there is a leak the smoke will come out of it. All it takes is a pin hole in these emission systems to screw it all up.