Intermittent Engine Idle Instability, Hard/No Restart or Decel Stalls, SES Lamp Illuminated, DTCs P0335, P0336, P0385, P0386 or P1599 may be Set (Diagnose and Repair)
| Subject: | Intermittent Engine Idle Instability, Hard/No Restart or Decel Stalls, SES Lamp Illuminated, DTCs P0335, P0336, P0385, P0386 or P1599 May Be Set (Diagnose and Repair) |
| Models: | 2000-2001 Cadillac DeVille, Eldorado, Seville |
| 2001 Oldsmobile Aurora |
| with 4.0L or 4.6L Engine (VINs C, Y, 9 -- RPOs L47, LD8, L37) |
Condition
Some owners may comment on an intermittent engine idle speed stability concern, hard or no restart condition or a decel engine stall. This may also be accompanied by a Service Engine Soon light being illuminated. Upon investigation, the PCM may indicate one of the following DTC codes: P0335, P0336, P0385, P0386 or P1599.
Cause
The above conditions may be caused by multiple concerns with the crank sensor or the PCM.
Correction
If the vehicle has any of the crank sensor codes P0335, P0336, P0385, or P0386 set, then the following should be done:
| • | Inspect both of the crank sensor terminals for signs of poor connection or corrosion of both crank sensors. Pin drag test all four terminals. |
| • | Inspect the crank sensor circuit wires for signs of damage. |
| • | Inspect the crank sensor circuits at the PCM for poor connections. The crank sensor terminals should also be drag tested. |
| • | Remove the crank sensors and check for any debris on the sensor. |
| • | Verify crank sensor location (A on the bottom and B on the top) and verify that the sensor circuit wires are in the correct cavities. |
| • | Inspect the date code on the sensor. If it is before 0276, replace the crank shaft sensor and perform case learn. |
| • | If the date code is past 0276, verify the PCM grounds. A voltage drop test should be less than 20 mV. |
| • | If the PCM ground circuit verification is acceptable, then follow published PCM diagnostics. |
If the vehicle has an idle or decel stall, or near stall concern and only has DTC P1599 set, then the following should be done:
| • | Verify the system power and ground connections for the PCM. |
| • | Verify crank sensor location (A on the bottom and B on the top) and verify that the sensor circuit wires are in the correct cavities in the harness. |
| • | Remove the crank sensors and check for any debris on the sensor. |
| • | Verify that the fuel pressure regulator is not leaking fuel past the diaphragm. |
| • | Perform the injector balance drop test and verify even pressure drops on all injectors. |
| • | Inspect and clean the EGR passages, as necessary. |
| • | Inspect and clean the IAC passages, as necessary. |
Parts Information
Part Number | Description | Qty |
|---|---|---|
12559529 | Crankshaft Position Sensor - Upper | 1 |
12559530 | Crankshaft Position Sensor - Lower | 1 |
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation | Description | Labor Time |
|---|---|---|
J4355 | Sensor, Crankshaft Position - Replace | Use Published Labor Operation Time |
J5650 | Injectors, Fuel - Replace | Use Published Labor Operation Time for Fuel Injector Drop Test |
J6360 | Module, Powertrain Control - Replace | Use Published Labor Operation Time |
