Seeking Advice on Cold Start, Unsteady Engine, and Power Loss Issues in a 2009 Hyundai Matrix

Hey there, sounds a lot like a situation I had with my 2011 Hyundai i30 a while ago. Just for context, I'm not exactly an automotive expert, but I've dealt with a few things over the years, just some experience, you might say. The symptoms I experienced were pretty identical to yours. Turned out, my problem was a defective fuel pressure regulator - had the exact symptoms that you're describing now. I had to take my lady to a local workshop I trust. They ran some diagnostics and confirmed my suspicions. The repair cost me about €250, not the cheapest day out, but certainly cleared up my issues. Seems like a similar solution might help in your case, but you'll need a professional diagnosis to be sure. By the way, do you happen to know your car's mileage and any previous related repairs? This info could help to pic a clearer picture. Best of luck getting it sorted.

Hey, thanks for the info! Good to hear from someone who dealt with something similar. It gives me a starting point to consider. About the mileage, it's at 65762 KM. Never had any engine-related repairs done before since my last service, just regular maintenance tasks. I'm thinking of heading to my trusty local mechanic for a comprehensive check next week. But till then, I'll keep scanning this thread hoping for more insight. Appreciate your help, dude.

No worries! Given that your Hyundai Matrix doesn't have a lot of mileage on it and has never had engine-related repairs, it's a bit unusual to face such problems, but hey, nothing's completely foolproof, right? My suggestion is, definitely get your trusty local mechanic to thoroughly check it. There could be numerous reasons causing these problems - hard starting could be due to a weak battery, black smoke is generally caused by a bad air-fuel balance or clogged fuel injectors, loss of engine power could be the result of bad spark plugs or a clogged fuel filter, and so on. Not to scare you, just trying to give you a sense of possible causes based on my experience. Hope you don't have to face too hefty a bill and your ride is back in top shape soon. Keep us updated on how it goes, will ya? All the best!

Thanks a ton! Your detailed explanation puts things into perspective. I guess it's hard to pinpoint without a thorough check as you suggested. I'll definitely bring up these points with my mechanic and hope it won't leave a hole in my wallet. Much appreciate your helpful and positive remarks, dude! Will surely keep you all in the loop once it's sorted. Fingers crossed! Cheers!