Have 2002 vue with po421,po431,po171,po174 - 2002 Saturn VUE

SOURCE: po171 and po174 is this an intake manifold gasket

if its a 6 cylinder it could have loose intake plenum bolts inside the intake causing a internal leak,,,and or a mass air flow sensor,but not a standard intake leak ,there is a tech service bulletin for this at saturn

Jeremiah Meyer

• 204 Answers
• Posted on Dec 06, 2008

SOURCE: check eng light with code po431 replased ox/sensors

P0431 is Warm Up Catalyst Efficiency Below Threshold (Bank 2). What is happening is this....the O2 sensor downstream of the Catalytic Converter is detecting the Converter is not working as efficiently as it should be (according to your cars specifications). 3 main causes of this is 1.) Defective O2 Sensor (which in your case elminates this one) 2.) Catalytic Converter is no longer functioning properly. or 3.) There is an exhaust leak. You will not notice any driveablitiy problems, however, you may get a rough/hard idle when its cold out. I would take your car to an exhaust shop and have them do a free exhaust system inspection. Alot of places like Midas/Mieneke Car Center/Monroe Muffler to name a few do these checks for free. Thanks for Using FixYa!

Sincerely,

JC

Harvey N Tawatao

• 3854 Answers
• Posted on Nov 08, 2009

SOURCE: i have a 2003 saturn Vue AWD V6 i'm getting error codes

PO700 is a code telling you there are codes in the TCM of some late model cars where the Transmission control module has been removed from the PCM the vehicles main computer , And basically it happens when the TCM has a issue within itself or the transmission that sets a code and it sends a request for the PCM to illuminate the SES or CHECK engine light. To get at the TCM codes requires in most cases the most up to date scanner software purchased after the cars model year and as of yet is still a little iffy. Standard OBD11 scanners will generally not be able to see these codes.

P0335 (Crankshaft Position Sensor A Circuit Malfunction) first disconnect the CKP itself and inspect the connector and terminals for corrosion. It should be clean and dry. Make sure the weather-tite seal on the connector is in place, uncontaminated and undamaged.
Resistance of the CKP should be 500-900 ohms.
If all good, trace the CKP harness upwards as far as you can (until it enters the main harness) and make sure you don't have any "rub-through" or spots where the wiring appears damaged.

DTC P0421 Warm Up Catalyst Efficiency Below Threshold (Bank 1)
DTC P0431 Warm Up Catalyst Efficiency Below Threshold (Bank 2)
Its too coincidental for both catcons to fault so there's something in common to this error (I feel is) upstream. First there's a V6 engine with separate sets of cylinder banks serving separate catcons with separate pairs of O2 sensors. For both rear sensors to come up simultaneously indicating low efficiency and "runs fine but strong exhaust smell, maybe running rich(?)" suggests a component in common to both cylinder banks; maf, map, iat, ects, tpp, etc.. Any one of these parts plays a role in the overall effect of a running engine and most likely needs monitoring while the engine's running with either Saturn's Tech-tool II or better readers/scanners capable of displaying live data to discern subtle faults translating to either a constantly rich or leaned out condition, abnormal running. Without other error codes to go by, there may be no choice than to seek Saturn diagnostic services other than a local expert capable of interpreting all the information from live data displayed onto a graphics screen to read from all the sensors. Diagnostic specialists.

P2119- THROTTLE CLOSED POSITION PERFORMANCE
Possible causes of DTC P2119: Weak throttle body return springs
Throttle plate sticking due to carbon build-up.

P0102 code relates to the Mass Air Flow (MAF) Sensor. The mass airflow sensor measures the speed and density of the air entering the intake manifold. The engine computer converts this input to a Mass of air per unit time to correctly fuel the engine. the code P0102 will set if the MAF sensor signal voltage is less then 0.20volts.

Code P0507 will set if the actual idle speed is greater then 200RPM from what the engine computer has commanded. Possible causes for this code: P0507 is high idle when the PCM wants lower. If you have the 1.9 LT SOHC engine in the 2000-2002 year range this is normal caused by a leaking intake gasket. Can be other sources of vacuum leak or something else that keeps the RPM up when it should not. It may be the Idle Air Control valve sticking.

The other two codes P037 and P044 i an not sure and the code P057 was a guess of P0507 since it's seams to be in the area where the problem is . The P0404 i am guessing it's going to be EVAP problem like a lose or bad gas cap. P0370 is (ECM) replicates the signal received from the crankshaft position (CKP) sensor. This signal is sent to the fuel injection control module (FICM) through the engine speed signal circuit. The FICM uses this replicated signal to generate injection current and control the recharge of the fuel injection high voltage circuits. When cranking, the FICM has full control of the fuel injectors. The only input the FICM uses at this time is the engine speed signal from the ECM. The FICM monitors the signal along with the injection request signals from the ECM after the engine is running. If there is a problem with this signal, a DTC could set.

Start with the simple and clean the Idle Air Control (IAC) valve, and the Mass Air Flow (MAF) sensor. This may help the P0421, P0431. and then check the crank shaft sensor wire harness and replace the sensor, which should take care of the P0370. *** for the P0404, check the gas cap if not replace it. Good luck and keep me posted.

Johnny Brown

• 5763 Answers
• Posted on Nov 10, 2010

SOURCE: Getting codes PO431, PO421, PO128

2003 saturn vue, we dont have the engine size, the codes should be and are the same, po 128 means; cooling temp is out of spec, make sure the coolant is full, then replace the coolant emp sensor and make sure the connection is good, i would also replace the thermostant, this is a common code on these and most of the time its the coolant temp sensor or thermostant, ive learned to replace then both to avoid future engine lights with code po128. next we will check the code # po421, this code is that the computer sees that the cat converters are taking to long to warm up, code po 431 is also the same as po421, this code is related to the thermostant and sensor, the sensor give the computer the wrong temp readings and then the compuetr thinks the engine is hotter than it is and thinks the converters should be also hot like the motor but the coolant temp is giving a false reading, if you replace the coolant temp sensor and the thermostant and fill coolant , then reset the light and you will solve the problem, i hope this is helpful, also the sensor is located to the right of the engine if you are standing in front of the motor, heres a picture of the sensor, remember to check connector heres a pic of the connector, good luck.

SOURCE: 03 saturn vue v6 3.0L

The codes are the 'system is too lean' on both banks (each side of the engine). Sounds like you may have 1 or more injectors not working correctly. They may have been clogged up and not giving enough fuel to the engine. You could try a good fuel injector cleaner like Berryman's Chemtool B-12 in the gas tank, but the injectors maybe too stopped up to cleared by this cleaner, but it's cheaper to try it first. It may take a can or two to get any results, I put 1 in my tank every 6 months to keep the injectors clean. You know the gas we buy is near perfect and the junk they add just messes everything up.