Seeking Advice on Troubleshooting High Fuel Consumption and Engine Issues in 2010 Nissan Serena Gasoline Model

Hey, I've had a somewhat similar issue with my 2008 Nissan Almera, and by no means am I an expert but I have some experience tinkering with cars. Turns out, it wasn't a Fuel composition error at all, but a defective cable/plug that was the culprit in my case. My vehicle was behaving pretty erratically too, with similar symptoms as yours. Took it to the local workshop, and man are those guys good. We went through the usual checks, and then they did a detailed inspection. Identified the defective cable and plug, got them replaced (cost me 95 Euro), and my ride was back to being its smooth self again. But of course, every problem is unique, right? So, it would be best to get more info about your vehicle in order to give much better advice. Can you share details like mileage, servicing history, or changes in fuel type, if any? It could go a long way in figuring out the real issue with your Nissan. Good luck! Keep us updated.

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Hey there, Appreciate the input! Interesting to know it was a cable/plug issue with your Almera. Makes me think I should expand my options a bit and not get hung up on the fuel composition thing. As for my Nissan detail, I've racked up about 145678 km on the odometer, and have always stuck to gasoline, no changes in fuel type. The latest service was done recently, just a regular one, no significant repairs or replacements. Based on that info, if you've got any more thoughts, I'm all ears! Thanks again for the advice, this community is awesome.

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Hey again, With that kind of mileage on your Serena, there are several possibilities we could look into. Based on my experience and that kind of mileage, I would consider checking your injectors as they could be causing the problems you described. Dirty or failing injectors can cause black smoke, poor fuel economy, and potentially an unstable engine. Ideally, they should be inspected every 80-100k km. A good cleaning might solve the problem, but failing ones need to be replaced - remember, it's always cheaper to sort these issues out sooner rather than later. Also, those intermittent engine shutdowns and the glowing check engine light could point to a faulty Engine Control Unit (ECU). Again I would recommend taking it to a local workshop for a proper diagnosis. I know it might sound tedious, but sometimes the most straightforward check can reveal something significantly wrong. I hope this helps. Keep us informed!

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Hey again, Thanks a bunch for the suggestions! Never considered the injectors as a possible cause, and your advice about sorting issues sooner rather than later really hit home. I'll definitely be looking into them and the ECU as well. It seems you've armed me with enough leads to give the pros at the local garage a run for their money, haha! You’re right about workshop visits being tedious but necessary, better safe than sorry I say. I'll get my Nissan checked out thoroughly and let you guys know how it pans out. Thanks again for all the help, really appreciate it! It's people like you that make this community such a great resource for folks like me. Cheers!

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