Seeking Advice on 2015 Fiat Siena's Engine Light, Fuel Efficiency, and Exhaust Issues

Hey! I noticed something similar with my 2013 Fiat Ducato not too long ago, we're basically in the same boat. Between you and me, I'm no car expert, but I got some experience under my hood. Personally, I took my ride to a local workshop. They identified the problem as a defective electric switching valve. It set me back 140 Euro, but did the job. Thing's been running smooth ever since. That said, every car's a bit different. To give you more targeted advice, I'd need to know about any recent changes or work done on your Siena. Did you replace or repair anything recently? Looking forward to hearing back from you.

Hey there! Yep, it seems we're in the same murky waters my. Recently, all that's been done is just the regular oil change and replacing the air filter at my last service, which was at 31924 km. Nothing big or related to the engine as such. Does that info help you out? Interested to hear if your advice changes now. Thanks for the personal experience and advice, really handy to get some insights from someone who already sailed through this. Could totally do without this 140 euro setback though, fingers crossed it's nothin' too major, haha!

Hey! Just caught your message. Honestly, it sounds like we're pretty much singing to the same hymn here. Just like you, I'd been keeping up with the regular maintenance—oil change, air filter swaps, you name it. Still, that pesky light came on. I guess sometimes these things just have their own minds, eh? If it was a recent switch of oil or air filter brand, then I might've wondered if that was the culprit. But given your situation, it doesn't really sound like you've gone down that route. Anywho, despite not wanting to sound like a broken record, I still stand by my previous advice. Take your car into a shop, have them give it a proper look over, focusing on the secondary air control valve. They should be able to tell you if it's gone defective. It ain't ideal in the pocket, I know, but I reckon it's your best bet. If anything, you've got some experience on me—your Siena's a couple years younger than my Ducato, maybe she'll be kinder to you. Fingers crossed for ya! Let me know how you get on, yeah?

Alright! Seems like the car gods are testing us, aren't they? You've convinced me, though. I'll take it to the workshop and have them check out the secondary air control valve for sure. Hope they don't make a major dent in my pocket, but what is it they say about paying the cost to be the boss, right? I'll pray to the car gods for me and you, maybe they'll have mercy on my younger Siena. You've been a great help, genuinely appreciate it! I'll swing by and let you know what went down at the workshop. Thanks a ton, and I raise my garage beer in toast to you, cheers! Let us survive these car shenanigans, haha!