HA: Adaptive Fuel

HA: Introduction

HA1 CHECK FOR OTHER DIAGNOSTIC TROUBLE CODES (DTCS)

DTC	HO2S Orientation	Fault Definition
181	Right or Rear	Rich limit reached.
183	Right or Rear	Rich limit reached at idle.
189	Left or Front	Rich limit reached.
192	Left or Front	Rich limit reached at idle.
These DTCs indicate the system is running lean, although strategy adjusted it to Max. rich.
179	Right or Rear	Lean limit reached.
182	Right or Rear	Lean limit reached at idle.
188	Left or Front	Lean limit reached.
191	Left or Front	Lean limit reached at idle.
These DTCs indicate that the system is running rich, although strategy adjusted it to Max. lean.



• Possible Causes:
• Fuel pressure.
• Fuel injector.
• Air intake.
• MAP sensor.
• Fuel injector electrical circuit.
• Fuel filter.
• Vacuum.
• Air filter.

HA2 CHECK FUEL PRESSURE

 WARNING: THE FUEL SYSTEM WILL REMAIN PRESSURIZED WHEN ENGINE IS NOT RUNNING. TO PREVENT INJURY OR FIRE, USE CAUTION WHEN WORKING ON THE FUEL SYSTEM.

• Key off.
• Install fuel pressure gauge.
• Verify that manifold vacuum is connected to the fuel pressure regulator if applicable.
• Start and run engine at idle. Note fuel pressure.
• Refer to Fuel Pressure Specification Table.

HA3 CHECK SYSTEM'S ABILITY TO HOLD FUEL PRESSURE

• Cycle the key on and off several times. Note the fuel pressure.
• Visually look for fuel leaking at the injector O-ring, fuel pressure regulator, and the fuel lines to the fuel charging assembly. Service as necessary.

HA4 CHECK MAP/BARO FREQUENCY

• Key off.
• Connect MAP/BARO tester.
• Key on.
• Refer to MAP/BARO Frequency Charts on this Pinpoint Test's cover page (also Pinpoint Test DF's cover pages) to check MAP/BARO frequency. It may be necessary to measure several known good MAP/BARO sensors on available vehicles to determine area's typical reading for that day.

HA5 DIAGNOSTIC TEST MODE (DTM): MFI ENGINES

• Connect tachometer to engine. Run engine at idle.
• Disconnect and reconnect the injectors one at a time: note rpm drop for each injector.

Note: IAC will attempt to re-establish rpm.

HA6 DIAGNOSTIC TEST MODE (DTM):
SFI ENGINES

The DTM switches each injector OFF and ON one at a time. Diagnostic Trouble Codes (DTC) correspond to the cylinder number (i.e., DTC 30 indicates a problem with cylinder No. 3, a DTC 90 indicates a pass). The DTM is designed to aid in the detection of a weak or non-contributing cylinder. The Pinpoint Test Steps are designed to isolate only EEC related problems.

Refer to Quick Test Appendix, Section 5A, for detailed information about DTM.

• Run the Engine Running Self-Test.
• After the last repeated code, wait 5-10 seconds.
• "Goose" throttle lightly (not wide-open-throttle).
• DTM will be performed. Time of test is 2-3 minutes.

HA7 CHECK RESISTANCE OF INJECTOR(S) AND HARNESS MFI ENGINES.

• Key off.
• Disconnect Powertrain Control Module (PCM). Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.

Note: This erases Continuous Memory.

• Install breakout box, leave PCM disconnected.
• Measure resistance of INJECTOR BANK 1 between Test Pin 37 and Test Pin 58 at the breakout box. Record resistance.
• Measure resistance of INJECTOR BANK 2 between Test Pin 37 and Test Pin 59 at the breakout box. Record resistance.
• Refer to Injector Resistance Specification Table 1.

HA8 CHECK RESISTANCE OF INJECTOR(S) AND HARNESS SFI ENGINES

• Key off.
• Disconnect Powertrain Control Module (PCM). Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.

Note: This erases Continuous Memory.

• Install breakout box, leave PCM disconnected.
• Measure resistance between the suspect INJECTOR circuit Test Pin and Test Pin 37 at the breakout box. Record resistance.

HA9 CHECK CONTINUITY OF FUEL INJECTOR HARNESS

• Key off.
• Breakout box installed, PCM disconnected.
• Disconnect injector vehicle harness connector at the suspect injector.
• Measure resistance between Test Pin 37/57 at the breakout box and the VPWR pin at the injector vehicle harness connector.
• Refer to the Pinpoint Test H Schematic for the appropriate injector pin identification.
• Measure resistance between the injector test pin(s) at the breakout box and the same injector circuit signal pin at the each injector vehicle harness connector.

HA10 CHECK INJECTOR HARNESS CIRCUIT FOR SHORT TO POWER OR GROUND

• Key off.
• Breakout box installed, PCM disconnected.
• Suspect fuel injector vehicle harness disconnected.
• Refer to the Pinpoint Test H Schematic for the appropriate injector pin identification.
• Measure resistance between the injector test pin(s) and Test Pins 37/57, 40, 46 and 60 at the breakout box.
• Measure resistance between the injector test pin(s) at the breakout box and chassis ground.

HA11 ISOLATE FAULTY INJECTOR CIRCUIT

• Key off.
• Breakout box installed, PCM disconnected.
• Disconnect all injectors on suspect bank.
• DVOM on 200 ohm scale.
• Connect one injector and measure resistance between Test Pin 37 and either Test Pin 58 or 59, as appropriate.
• Disconnect that injector and repeat process for each of the remaining injectors.
• Refer to Injector Resistance Specification Table 2.

HA12 CHECK INJECTOR DRIVER SIGNAL

Requires standard non-powered 12 volt test lamp.

• Key off.
• Breakout box installed.
• Connect PCM to breakout box.
• For MFI:
• Connect test lamp between Test Pin 37 and Test Pin 58 at the breakout box.
• Connect test lamp between Test Pin 37 and 59 at the breakout box.
• For SFI:
• Connect test lamp between Test Pin 37 and the suspect injectors Test Pin at the breakout box.
• Crank or start engine.

Note: Properly operating systems will show a dim glow on the lamp.