96 Ford Windstar GL 3.8L with P1537, P1538, P0303, P0305 Codes - Van Dies at Turns or Stops, Lagging Acceleration, Unreliable Speedometer
I'm experiencing several OBD2 diagnostic codes on my 1996 Ford Windstar GL 3.8L: P1537, P1538, P0303, and P0305. The vehicle occasionally dies while turning, reversing, or at a stoplight. During acceleration, I notice a lag—sometimes the engine resists speeding up as if it's not responding properly. Additionally, the speedometer needle fluctuates erratically, making it difficult to know my actual speed. Could anyone explain what these codes mean and how they might be related to the symptoms? Any technical insight or troubleshooting steps would be greatly appreciated.
The P030X codes indicate misfires on cylinders 3 and 5. For more details, see: http://www.obd-codes.com/p0305. P1537 refers to an Intake Manifold Runner Control (IMRC) malfunction on Bank #1, where the IMRC is stuck open. P1538 indicates a similar issue on Bank #2, with the IMRC also stuck open. These issues can lead to poor engine performance, hesitation during acceleration, and unstable idle—consistent with your symptoms.