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Engine Controls - 2.2L (L61) - Introduction: Diagnosis Saturn ION I

Testing & Diagnostics 2 illustrations ~1244 words

Diagnostic Trouble Code (DTC) Type(s)

Diagnostic Trouble Code (DTC)AutoManual
P0030BB
P0036BB
P0068AA
P0101BB
P0102BB
P0103BB
P0106BB
P0107BB
P0108BB
P0112BB
P0113BB
P0117BB
P0118BB
P0120AA
P0121BB
P0122AA
P0123AA
P0125BB
P0128BB
P0130BB
P0131BB
P0132BB
P0133BB
P0134BB
P0135BB
P0136BB
P0137BB
P0138BB
P0140BB
P0141BB
P0201-P0204BB
P0220AA
P0222AA
P0223AA
P0230CC
P0300Type B EMISSION Type A CATALYSTB
P0315BB
P0325BB
P0326BB
P0327BB
P0335BB
P0336BB
P0340BB
P0341BB
P0411BB
P0412BB
P0418BB
P0420AA
P0442AA
P0443BB
P0446AA
P0449BB
P0452AA
P0453AA
P0455BB
P0461CC
P0462CC
P0463CC
P0480BB
P0496BB
P0502BB
P0503BB
P0506BB
P0507BB
P0520CC
P0532CC
P0533CC
P0562CC
P0563CC
P0572CC
P0573CC
P0601AA
P0602AA
P0603CC
P0604AA
P0606AA
P0607CC
P0621CC
P0622CC
P0641AA
P0650BB
P0651AA
P0700AA
P0703CC
P0719CC
P0722BB
P0723BB
P0724CC
P1101BB
P1106CC
P1107CC
P1111CC
P1112CC
P1114CC
P1115CC
P1133BB
P1134BB
P1516AA
P1545CC
P1621AA
P1630CC
P1631CC
P1633CC
P1680AA
P1681AA
P1682CC
P1700CC
P1887BB
P2101AA
P2119CC
P2120AA
P2122AA
P2123AA
P2125AA
P2127AA
P2128AA
P2135AA
P2138AA
P2176AA
P2430BB
P2431BB
P2432BB
P2433BB
P2610BB

Diagnostic Trouble Code (DTC) Type(s)

Scheme 20

Scheme 20: Emission Hose Routing Diagram
CalloutComponent Name
1EVAP Canister Purge Solenoid Valve
2To EVAP Canister
3Throttle Body
4To Intake Manifold

Scheme 21

Scheme 21: Evaporative Emissions (EVAP) Hose Routing Diagram
CalloutComponent Name
1Fuel Tank Pressure (FTP) Sensor
2Fuel Tank
3Evaporative Emission (EVAP) Vent Solenoid Valve
4EVAP Canister
5EVAP Service Port
6EVAP Purge Solenoid Valve
7Fill Limit Vent Valve (FLVV)
8Grade Vent Valve

Cleaning and Inspection Procedure

  1. If using the original IAC valve, perform the following inspection and cleaning procedure: Clean the IAC valve sealing surface, pintle valve seat and air passage in the throttle body. Whenever the air passages have heavy deposits, remove the throttle body for a complete cleaning. Refer to «Throttle Body Cleaning Procedure»(ref-196955-S34051927132005101000000) . The IAC valve may be cleaned by using a shop towel or small parts cleaning brush to remove heavy deposits. Shiny spots on the pintle or seat are normal, and not an indication of a misaligned pintle shaft. Inspect the IAC valve seal for cuts, cracks or distortion. Replace the IAC valve if the seal is damaged.
  2. Whenever installing a new IAC valve, replace the valve with an identical part. The IAC valve pintle shape and diameter are specific to this application.
  3. Compare the distance between the tip, or the pintle, and the mounting flange of the new and old IAC valves. Use finger pressure to slowly retract the pintle of the new valve to the distance of the old. This will not cause damage to the new IAC valve but is critical for installation.

Inspection Procedure

  1. Turn OFF the ignition.
  2. Remove the EVAP canister purge valve. Refer to «Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement»(ref-196955-S26441694032005101000000) .
  3. Lightly tap the EVAP canister purge valve on a hard surface.
  4. Inspect for carbon particles exiting either of the vacuum ports. If no carbon particles were detected, but a blockage was detected during a diagnostic procedure, install the original EVAP canister purge valve. Continue with the cleaning procedure. If carbon particles are found during the inspection procedure, continue with the cleaning procedure. If a diagnostic procedure directed you to replace the EVAP canister purge valve and no carbon particles were detected, replace the EVAP canister purge valve. Return to the published service procedure.

Spark Plug Visual Inspection

  1. Normal operation-Brown to grayish-tan with small amounts of white powdery deposits are normal combustion by-products from fuels with additives.
  2. Carbon Fouled-Dry, fluffy black carbon, or soot caused by the following conditions: Rich fuel mixtures Leaking fuel injectors Excessive fuel pressure Restricted air filter element Incorrect combustion Reduced ignition system voltage output Weak coils Worn ignition wires Incorrect spark plug gap Excessive idling or slow speeds under light loads can keep spark plug temperatures so low that normal combustion deposits may not burn off.
  3. Deposit Fouling-Oil, coolant, or additives that include substances such as silicone, very white coating, reduces the spark intensity. Most powdery deposits will not effect spark intensity unless they form into a glazing over the electrode.

Diagnostic Trouble Codes (DTCs)

The ECM is programmed with test routines that test the operation of the various systems the ECM controls. Some tests monitor internal ECM functions. Many tests are run continuously. Other tests run only under specific conditions, referred to as Conditions for Running the DTC. When the vehicle is operating within the conditions for running a particular test, the ECM monitors certain parameters and determines if the values are within an expected range. The parameters and values considered outside the range of normal operation are listed as Conditions for Setting the DTC. When the Conditions for Setting the DTC occur, the ECM executes the Action Taken When the DTC Sets. Some DTCs alert the driver via the MIL or a message. Other DTCs do not trigger a driver warning, but are stored in memory. The ECM also saves data and input parameters when most DTCs are set. This data is stored in the Freeze Frame and/or Failure Records.

The DTCs are categorized by type. The DTC type is determined by the MIL operation and the manner in which the fault data is stored when a particular DTC fails. In some cases there may be exceptions to this structure. Therefore, when diagnosing the system it is important to read the Action Taken When the DTC Sets and the Conditions for Clearing the DTC in the supporting text.

There are different types of DTCs and different actions taken when the DTCs set. Refer to Diagnostic Trouble Code (DTC) Type Definitions for a description of the general characteristics of each DTC type.

Large Leak Test

This tests for large leaks and blockages in the evaporative emission (EVAP) system. The control module commands the EVAP vent solenoid valve ON and commands the EVAP purge solenoid valve ON, with the engine running, allowing engine vacuum into the EVAP system. The control module monitors the fuel tank pressure (FTP) sensor voltage to verify that the system is able to reach a predetermined level of vacuum within a set amount of time. The control module then commands the EVAP purge solenoid valve OFF, sealing the system, and monitors the vacuum level for decay. If the control module does not detect that the predetermined vacuum level was achieved, or the vacuum decay rate is more than a calibrated level on 2 consecutive tests, DTC P0455 will set.

Small Leak Test

The engine off natural vacuum (EONV) diagnostic is the small-leak detection diagnostic for the evaporative emission (EVAP) system. While previous leak detection methods were performed with the engine running, the EONV diagnostic monitors the EVAP system pressure or vacuum with the key OFF. Because of this, it may be normal for the control module to remain active for up to 40 minutes after the engine is turned OFF. This is important to remember when performing a parasitic draw test on vehicles equipped with EONV.

The EONV diagnostic utilizes the temperature changes in the fuel tank immediately following a drive cycle to use the naturally occurring vacuum or pressure in the fuel tank. When the vehicle is driven, the temperature rises in the tank. After the vehicle is parked, the temperature in the tank continues to rise for a period of time, then start to drop. The EONV diagnostic relies on this temperature change and it's corresponding pressure change to determine if an EVAP system leak is present.

The EONV diagnostic is designed to detect leaks as small as 0.51 mm (0.02 in). The diagnostic can determine if a small leak is present based on vacuum or pressure readings in the EVAP system. When the system is sealed, a finite amount of pressure or vacuum will be observed. When a 0.51 mm (0.02 in) leak is present, often little or no pressure or vacuum is observed. If the test reports a failing value, DTC P0442 will set.

Canister Vent Restriction Test

If the evaporative emission (EVAP) vent system is restricted, fuel vapors will not be properly purged from the EVAP canister. The control module tests this by commanding the EVAP purge solenoid valve ON, commanding the EVAP vent solenoid valve OFF, and monitoring the fuel tank pressure (FTP) sensor for an increase in vacuum. If the vacuum increases more than a calibrated value, DTC P0446 will set.

Purge Solenoid Leak Test

If the evaporative emission (EVAP) purge solenoid valve does not seal properly, fuel vapors could enter the engine at an undesired time, causing driveability concerns. The control module tests for this by commanding the EVAP purge solenoid valve OFF and the vent solenoid valve ON, sealing the system, and monitors the fuel tank pressure (FTP) for an increase in vacuum. If the control module detects that the EVAP system vacuum increases above a calibrated value, DTC P0496 will set.