I have a 1998 GMC 3500, the engine is not the original engine but I believe it's a 5.7L L31. My crankshaft sensor has gone out but the only one any parts store has is to big to go in the hole mine came out of, What should I do?
Is it possible that my vehicle missed some sort of upgrade or recall and now the new sensors are only made for vehicles that have been modified to fix the problem? Any help would be GREATLY appreciated as it's my only vehicle and I need it to drive back and forth to work and pick up kids from school. Thanks.
Here was a TSB for your 5.7L Vortec L31, it will have the replacement part number to your Crankshaft sensor.
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 00-06-04-014
Date: April, 2000
TECHNICAL
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 SIT 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
^ "No" 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
Crankshaft Position Sensor, P/N 10456607
Good luck and have the Auto store recheck for the right part.
