VW Jetta Hybrid Fuel System Issues: Common Fix Guide

I had a similar issue with my 2018 VW Passat Hybrid last summer. Having some experience with hybrid vehicles and general car maintenance, I recognized those exact symptoms. After thorough automotive diagnosis at my regular workshop, they discovered it wasnt actually the fuel pump but rather a faulty wiring connection to the fuel injector system. The cable connection had deteriorated over time, causing intermittent fuel delivery issues and affecting car performance. The repair was relatively straightforward once properly diagnosed. The total cost came to 95€ including labor, which was reasonable considering the symptoms matched a potential pump failure, which would have been much more expensive. The fix took about 2 hours and completely resolved the rough running, stalling, and starting issues. Fuel consumption returned to normal immediately after the repair. Before offering more specific advice about your situation, could you share: Current mileage on your Jetta, Any recent maintenance history, Whether you notice these issues more in specific conditions (cold starts, hot weather, etc), Any additional warning lights or error codes, How long these symptoms have been occurring This information would help determine if youre dealing with the same underlying issue or something different in your fuel system.

Last service was done at 120000km. The error codes from my OBDII reader show P0087 and P0191, suggesting fuel rail pressure issues. I tried cleaning the fuel pressure sensor but the problem persists. The symptoms get noticeably worse during hot weather and mainly after the car sits for several hours. The rough running started about 3 weeks ago and has gradually gotten worse. The fuel delivery problems seem most severe during initial startup and when accelerating from a stop. Local repair shops are quoting between 400-600€ for a fuel pump replacement, but given the car performance issues, I want to be certain thats the actual problem before proceeding with such an expensive repair.

Thanks for providing those details about your Jetta. The error codes P0087 and P0191 definitely point toward fuel pressure issues, which matches what I experienced. However, in my case, after initially suspecting the fuel pump, it turned out the problem was more nuanced. While cleaning the fuel pressure sensor was a good first step, the symptoms you describe, especially worsening in hot weather and after sitting, strongly suggest checking the fuel pressure regulator. This part can often be overlooked when diagnosing engine stalling and rough running conditions. In my Jetta, the mechanics initially quoted me for a complete fuel pump replacement too. However, before proceeding, they performed a fuel pressure test which revealed the regulator was failing intermittently, causing similar car performance issues to what youre experiencing. The replacement regulator cost 180€ including labor, significantly less than a full pump replacement. The repair resolved all symptoms: the rough running, hard starts, and engine stalling completely disappeared. The check engine light cleared after the fix and fuel consumption returned to normal. Consider requesting a fuel pressure test specifically focusing on the regulator before committing to the more expensive pump replacement. This could save you considerable money while still resolving the fuel system problems.

Thanks for the detailed troubleshooting suggestions. The fuel pressure test focusing on the regulator makes a lot of sense, especially given how the symptoms match what you experienced. I just called a local shop and they can do the pressure test tomorrow for 60€. Much better to spend that first before jumping into a full fuel pump replacement. The fact that your repair cost was only 180€ for the regulator gives me hope this wont be as expensive as initially quoted. Ill make sure they check both the regulator and the wiring connections you mentioned, since either could cause these engine stalling issues. Really hoping to avoid the 600€ pump replacement if possible. Will follow up once I get the test results and know exactly whats causing the car performance problems. Thanks again for sharing your experience, its helping me make a more informed decision about the repairs.