Jeep Commander's Rough Idle Points to Bad EGR System

I experienced identical symptoms in my Jeep Grand Cherokee diesel (2019) last season. A gasket leak in the intake manifold was causing significant performance issues. The manifold pressure sensor readings were erratic, leading to engine performance problems similar to what you describe. The rough idle, power loss, and exhaust issues strongly suggest a manifold-related problem. In my case, the intake manifold had developed hairline cracks due to heat exposure, causing vacuum leaks. The manifold sensor was also giving false readings due to the leak. This was a serious issue requiring immediate attention. Left unchecked, it could lead to further engine damage and increased fuel consumption. The repair involved replacing the intake manifold assembly, gaskets, and sensor components. Key indicators that confirmed the manifold issue: Engine running extremely rough at idle, Drop in power under acceleration, Excessive exhaust smoke, Erratic manifold sensor readings, Check engine light activation Consider getting a second opinion from a shop specializing in diesel engines. The symptoms match a manifold problem too closely to ignore.

Had the exact same engine misfire and performance problems with my Commander last winter. After reading your post, it definitely sounds like the intake manifold issue I dealt with. The vacuum leak symptoms match perfectly, rough idle, power loss, and those heavy exhaust fumes. Got it fixed with a complete manifold replacement and new sensor setup, which solved the air intake problems completely. The engine runs smooth now with no more stalling or jerking. Just curious, did you end up getting it repaired? What did they charge you for the fix? Also wondering if youve noticed any other issues pop up since then?

Since getting the repair done, my Jeep runs perfectly. The initial diagnosis confirmed a defective intake manifold, which had developed serious scorching damage causing air leaks. The complete fix, including parts and labor, came to 1180 Euro. The repair included: New intake manifold assembly, Updated manifold sensor, Fresh gasket seals, System diagnostics, Labor costs No engine misfire issues or performance problems have occurred since the repair. The engine runs smoothly at all speeds now, with proper acceleration response and no more rough idling. The exhaust fumes are back to normal, and fuel efficiency has actually improved. The repair cost was worth it to prevent further engine damage. A failing intake manifold can lead to more serious issues if left unaddressed. The gasket leak particularly needed immediate attention to prevent damage to other engine components.

I finally took it to a diesel specialist mechanic after reading about similar manifold pressure issues online. The engine performance problems were getting worse, with constant engine misfires affecting daily driving. The mechanic found multiple vacuum leaks in the intake manifold, explaining the rough running and power loss. The repair bill came to 1350 Euro total, not cheap, but worth every cent. They replaced the entire manifold assembly, sensors, and all gaskets. The difference is incredible. No more jerking, stalling or thick exhaust fumes. The engine runs perfectly smooth now, even at idle. Fuel economy has improved significantly too. The check engine light hasnt come back since. My advice to others: dont wait if you notice similar symptoms. The vacuum leaks can cause more expensive engine damage if left unfixed. Finding a specialist who knows diesel engines made all the difference in my case.