Tech Tip: Dodge Neon Sport Code P0340 Intermittently – UnderhoodService

Tech Tip: Dodge Neon Sport Code P0340 Intermittently

Customer complains the vehicle bucks and misses intermittently while driving. Code P0340 is stored. This code may be caused by the camshaft position sensor.

Some 2004-’05 Dodge Neons will intermittently experience a P0340 code. Here are two fixes to consider.

Vehicle Application: 2004-’05 Neon 2.0L

Customer Concern: Bucks and misses intermittently while driving. Code P0340 is stored.

Potential Cause: Camshaft position (CMP) sensor.

Tests/Procedures
1. Unplug the CMP sensor to see if the symptoms can be duplicated.

2. If yes, inspect the connector and if OK, replace the CMP sensor.

Tech Notes: This engine would not run over 2,100 rpm with the CMP sensor unplugged. It would start but had very long crank time.


Vehicle Application:
2005 Neon 2.0L

Customer Concerns: Codes P0340 sets intermittently. Engine dies out for the customer; runs OK for a period of time, then customer has to drive a long time before it will act up again.

Potential Causes: CMP sensor.

Tests/Procedures
1. Monitor the 5-volt power supply (orange) to the CKP and the CMP. If it goes low when it acts up, unplug the vehicle speed sensor (VSS). The VSS shares the power supply circuit for the CKP and the CMP. Replace the VSS if that brings the voltage back up.

2. Verify both the CKP and the CMP signals with a labscope and compare to a normal pattern.

Courtesy of Identifix.

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