1998 Sebring V6 P1297 Diagnostic Help: Vacuum Leak, Fuel Rail, and Wiring Issues
I believe this vehicle is equipped with a 3.0L V6 engine, which is known to develop driveability issues over time. A common cause of the P1297 fault code is a vacuum leak at the lower intake manifold gasket. Additionally, the fuel rail features a non-return valve that can restrict fuel flow—though this is less likely given the vehicle appears to be running rich. Another potential issue involves the large harness routed across the thermostat housing, which has been documented to cause wire chafing and loss of reference signals. Given these factors, I strongly recommend conducting a thorough diagnostic check rather than relying on assumptions or guesswork. The P1297 code specifically relates to an oxygen sensor signal failure, often linked to vacuum system integrity or electrical interference in the intake area.
I've never encountered a vehicle with such persistent issues—this is becoming increasingly frustrating. The car now stalls when cold, and I can't get it to start. The flywheel turns manually, so the engine isn