P0298 Fault Code in 2007 Jeep Grand Cherokee 3.7L: Diagnosis and Solutions
I've recently developed a new diagnostic trouble code, P0298, in my 2007 Jeep Grand Cherokee 3.7L. This vehicle has been struggling with a persistent P0430 code for some time, which ultimately led to a failed inspection. I have already replaced two oxygen (O2) sensors and conducted a visual inspection of all vacuum lines for potential leaks. After clearing the codes, the issue returned the next day—now both P0430 and P0298 are present. This ongoing problem is making me lose confidence in my Jeep quickly. I'm seeking reliable advice on how to properly diagnose and resolve this issue, especially since the vehicle appears stock and has not undergone any modifications.
P0298 typically indicates an engine oil temperature (EOT) sensor or related issue. However, I'm unsure if this code applies to the 3.7L engine in my Jeep—could it be a misdiagnosis? Given that you've been working on O2 sensors, it's worth considering whether a catalytic converter issue might be contributing, possibly indicated by P2098 (post-catalyst oxygen sensor fault). Could you confirm which specific O2 sensors were replaced? Also, is your vehicle exactly stock with no modifications? A reliable scan tool that provides live data and allows graphing of O2 sensor voltages would greatly assist in identifying the root cause.