P0337: Crankshaft Position Sensor "A" Circuit Low Input
2 vehicles · 2 makes · $100-$500 repair
Most Reported On
P0337 is an OBD-II diagnostic trouble code meaning “Crankshaft Position Sensor "A" Circuit Low Input.” The crankshaft position (CKP) sensor watches a toothed reluctor wheel on the crankshaft and tells the engine computer exactly how fast the crank is spinning and where each piston is, which the computer needs to time spark and fuel injection. P0337 sets when the computer sees the sensor's signal voltage stuck near zero — below the expected range — usually because the sensor has failed or its wiring is open, shorted to ground, or corroded. You may notice hard starting, an engine that cranks but won't start, rough idle, stalling, or reduced power and fuel economy; on many vehicles the engine simply won't run while the fault is present. Ignoring it risks being stranded by a sudden no-start or a stall in traffic, so it should be diagnosed promptly. This code is most commonly reported on 1999-2009 Saab 9-5, and 1992-2005 Pontiac Bonneville, with repair costs ranging from $100 to $500.
Common Causes
Typical Repair Cost
Based on 2 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
To diagnose P0337, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
by ANCEL
A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).
- Read & clear engine codes
- View freeze frame data
- I/M readiness status
- No batteries or app needed
BlueDriver Pro Bluetooth Scanner
by BlueDriver
Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.
- Enhanced diagnostics (ABS, SRS, transmission)
- Repair Reports with verified fixes
- Smog check readiness
- Free app (iOS & Android)
LAUNCH CRP123X OBD-II Scanner
by LAUNCH
A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.
- Engine, transmission, ABS, SRS diagnostics
- Live data stream & graphing
- AutoVIN for vehicle identification
- Free lifetime updates via Wi-Fi
Autel MaxiCOM MK808S Diagnostic Tool
by Autel
Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.
- All-system diagnostics (25+ modules)
- Bi-directional control & active tests
- Oil reset, EPB, BMS, TPMS, injector coding
- 7-inch touchscreen with Android OS
As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.
FAQ
What does P0337 mean?
P0337 stands for "Crankshaft Position Sensor "A" Circuit Low Input." The crankshaft position (CKP) sensor watches a toothed reluctor wheel on the crankshaft and tells the engine computer exactly how fast the crank is spinning and where each piston is, which the computer needs to time spark and fuel injection. P0337 sets when the computer sees the sensor's signal voltage stuck near zero — below the expected range — usually because the sensor has failed or its wiring is open, shorted to ground, or corroded. You may notice hard starting, an engine that cranks but won't start, rough idle, stalling, or reduced power and fuel economy; on many vehicles the engine simply won't run while the fault is present. Ignoring it risks being stranded by a sudden no-start or a stall in traffic, so it should be diagnosed promptly.
What are the most common causes of P0337?
The most common causes of P0337 are: Failed crankshaft position sensor (the most common cause), Open, shorted-to-ground, or chafed wiring in the CKP sensor circuit, Loose, corroded, or damaged CKP sensor connector, Damaged, dirty, or missing-tooth reluctor (tone) ring on the crankshaft, Metal debris on the sensor's magnetic tip or incorrect sensor air gap, Low battery voltage or a weak starter producing an out-of-range signal during cranking, Faulty powertrain control module (rare). The specific cause varies by vehicle.
How much does it cost to fix P0337?
Repair costs for P0337 range from $100 to $500, depending on the vehicle and root cause.
Which vehicles are affected by P0337?
Au7o has documented P0337 across 2 vehicle models from 2 manufacturers: Pontiac, Saab.
Sources (8)
- ForumCrank Position Sensor Failure Symptoms | SaabCentral Forums
- ForumIntermittent Stall/No start condition | SaabCentral Forums
- articleSaab 9-5 Crankshaft Position Sensor Guide | Go-Parts.com
- articleAA1Car — Diagnosing the Buick (GM) 3800 V6 Engine: CKP sensor and ignition module no-start
- articleEasyAutoDiagnostics — How to Test the GM 3.8L Ignition Control Module and Crank Sensor (applies to Pontiac Bonneville 1993-2005)
- articleRepairPal — Engine Performance Problems Due to Crankshaft Position Sensor Failure: Pontiac Bonneville
- articleRepairPal — Engine Stalling Due to Mass Air Flow/Crankshaft Position Sensor Failure: Pontiac Bonneville (149 reports)
- ForumEdmunds Forums — Pontiac Bonneville Starting/Stalling/Ignition Problems (multi-page thread)
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.