Rough Diesel: Manifold Issues Cause Multiple Failures

Had almost the exact same issue with my 2013 Dodge 750 diesel last winter. Have some experience working on diesel engines, but this one required professional help. The symptoms matched yours perfectly, rough running, misfires, and that characteristic drop in power. The check engine light was constantly on, and the manifold pressure readings were all over the place. After running diagnostics, it turned out to be a serious vacuum leak caused by a scorched intake manifold. Took it to a specialized diesel workshop where they confirmed the intake manifold had developed cracks from excessive heat. They had to replace the entire manifold assembly and related gaskets. Total cost came to 1180€, but it solved all issues completely. Engine now runs smooth with proper power delivery. Before suggesting specific solutions, could you share: Current mileage on your engine, Any recent maintenance history, Specific error codes from the check engine light, Whether youve noticed any changes in fuel consumption This information would help determine if youre dealing with the same intake manifold problem I experienced. These symptoms can sometimes also indicate other issues with the fuel delivery system.

Thanks for sharing your experience. My Dodge shows 89445 KM and last service was 3 months ago where they changed oil and filters. The car manifold sensor readings from my diagnostic tool show irregular patterns matching your description exactly. During the last service, they didnt notice any vacuum leaks, but engine performance has deteriorated significantly since then. I checked the error codes this morning, getting P0299 and P0106 consistently, which point toward manifold pressure issues. Fuel consumption increased by about 15% over the past month. Think I will follow your advice and take it to a diesel specialist. The symptoms and error codes seem too similar to ignore. Would rather invest in proper repairs now than risk more extensive engine damage.

Thanks for the details, those mileage numbers and error codes are crucial info. On my 2013 Dodge 750, I initially tried band-aid fixes like cleaning the manifold and checking basic vacuum lines, but the engine misfire issues kept returning. The P0299/P0106 combo definitely confirms manifold pressure problems. When my car showed these same codes, the mechanic found hairline cracks in the manifold that were causing major vacuum leaks. These cracks typically start small but expand quickly due to heat cycles. After getting the full manifold replacement, pay attention to: Any gasket leaks around the new assembly, Changes in idle behavior, Manifold pressure readings staying consistent, Return to normal fuel consumption Make sure the shop pressure tests the whole system after repair. My mechanic found additional vacuum leaks in connecting hoses that werent obvious initially. Getting those fixed as part of the job prevented future issues. The total repair should cost similarly to what I paid unless prices have changed. Just ensure they use OEM parts for the manifold assembly, aftermarket options caused problems for other owners in our owners group.

Thanks for the comprehensive feedback. After seeing how similar our situations are, especially with those P0299 and P0106 codes linked to manifold pressure problems, I feel more confident about the next steps. The 15% increase in fuel consumption along with the worsening engine performance really matches your experience with vacuum leaks. My diagnostic readings showing irregular manifold sensor patterns basically confirm what you went through. Ill book it into a specialized diesel workshop this week. Given the check engine light issues and consistent misfires, waiting longer could lead to bigger problems. Good point about getting them to do a full pressure test, dont want to miss any hidden vacuum leaks that could cause issues later. Appreciate the heads up about requesting OEM parts for the manifold assembly and watching for gasket leaks after the repair. The repair cost around 1180€ seems reasonable considering the alternative could be major engine damage. Will update the forum once I get the work done and can confirm if it resolves all the symptoms like it did in your case.