| Subject: | No, Hard, or Slow Start, Backfire or "Kickback" During
Crank/Start, "Grinding" or Unusual Noises During Crank, DTC P0338 (Replace
Crankshaft Position Sensor) |
| Models: | 1999-2000 Cadillac Escalade |
| 1995-2000 Chevrolet and GMC S/T Models |
| 1996-2000 Chevrolet and GMC C/K, M/L , G, P Models |
| 1996-2000 Oldsmobile Bravada |
| with 4.3 L, 5.0 L, 5.7 L or 7.4 L Engine
(VINs W, X, M, R, J -- RPOs L35, LF6, L30, L31, L29) |
Condition
Some customers may comment on one or more of the following conditions:
| • | Backfire during crank/start |
| • | "Kickback" during crank/start |
| • | "Slow" or "hard" start/crank |
| • | "Grinding" or unusual noises during crank/start |
| • | Cracked or broken engine block at the starter boss |
| • | Broken starter drive housing |
| • | Broken starter ring gear on flywheel |
| • | Any combination of the above |
Cause
A condition may exist that allows the crankshaft position sensor to
command up to 50 extra degrees of spark advance during engine cranking only.
This in turn exposes the engine to higher than normal cylinder pressures which
may result in an inoperative condition to the starter drive housing, the engine
flywheel starter ring gear, or the engine block at the outside edge of the
starter boss.
Correction
Inspect for a stored powertrain DTC code P0338. This DTC will NOT illuminate
the "Service Engine Soon" light. If this code is stored, the Crankshaft Position
Sensor, P/N 10456607, MUST be replaced and the remaining components inspected
for damage (engine block at the starter boss, the starter drive housing, and
the engine flywheel starter ring gear).
Notice: When DTC code P0338 is set, failure to replace the Crankshaft Position
Sensor could result in repeated inoperative conditions of the starter or flywheel.
Important: Some flywheel wear is normal; broken or missing teeth and/or cracks,
are not normal.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use:
Labor Code
| Description
| Labor Time
|
J4355
| Sensor, Crankshaft Position - Replace
| Use Published Labor Time
|
