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LangRolf

Possible Fuel Filter Heater Defect in 2021 Kia Seltos Diesel: Symptoms and Solutions

Car won't start

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Longer cold start time

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Black smoke from exhaust on acceleration

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Check engine light on

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Engine shuts off by itself

Hey fellow car enthusiasts, I'm having some troubles with my Kia Seltos diesel 2021, currently clocking at 37451 KM. On acceleration, there's this nasty black smoke from the exhaust. The check engine light's on and, weirdly, the engine spontaneously turns off. Maybe it's unrelated, but it's also taking a bit more time to start in the cold and at times, it won't even start at all. Not an expert, but could this all be related to a potential fuel filter heater defect? Any of you experienced something similar with your vehicle and how was it handled at your mechanic? Really need some insights here before heading to a repair shop, considering a previous not-so-good experience. Thank you in advance for your suggestions! Cheers!

6 comment(s)


LudwigSpeedy

Hey there, I feel your pain. Had a similar issue with my 2018 Kia Sportage diesel, couldn't figure out what was up until I decided to get a thorough check at the garage. Turned out, it was indeed the fuel filter heater wiring harness/connector giving me a headache. To give you some context, the symptoms were almost exactly like yours - check engine light was lit up like a Christmas tree, engine cutting off at unusual, starting issues, you name it. And of course, that nasty black smoke giving me a hell of a scare on the road. The garage ran diagnostics and did a complete overhaul on the wiring harness/connector related to the fuel filter heater. One thing the mechanic mentioned was that it might seem like a small issue but actually it could lead to bigger, potentially serious problems if not attended to. So, my advice - don't hold back. Get your Seltos to the garage ASAP. It's better to be safe than sorry, especially when it involves something as intricate as the fuel system. Good luck! And don’t worry, we've both got good taste in cars, so here's hoping your Kia will be back in action in no time. Cheers!

LangRolf (Author)

Hey! Thanks for sharing your experience, dedicated mechanics are a blessing in disguise, aren't they? I never thought a fuel filter heater issue could raise such a hell. Just a quick one, do you remember what kind of sum I should expect from fixing this pesky bug? Also, since you got your Sportage fixed, did something else crop up or has she been behaving herself? Eagerly waiting for your response! Cheers!

Best Answer

LudwigSpeedy

Hey there! Ah, the bane of car repairs: the costs! When my Sportage was giving me fits, getting the fuel filter heater wiring harness/connector sorted cost me around 110 €. Not the cheapest fix but not the priciest either, considering it solved the problem. I'd be prepared for an estimate around there or maybe even a bit lower if you're lucky! Post repair, my Sportage has been a dream, no more black smoke or unusual engine issues. Since I had the fuel filter heater problem fixed, my baby has been purring like a kitten and there hasn't been a single hitch. *touches wood* So, don't you worry, once the bug is squashed, your Seltos should be running as smooth as before! Give me a shout if you have more questions, always here to help a fellow motorhead. Cheers!

LangRolf (Author)

Hey! Thanks again for being so helpful, I really appreciate it! You've lifted a weight off my shoulders. I am heading straight to the garage tomorrow without any further ado. Hoping for the best and keeping my fingers crossed my Seltos returns to her standard smooth running, just like your Sportage! You can bet I'll be back here if there are any more hitches. Till then, happy and safe driving! Cheers!

CMario1007

I have a BMW 320d and it has the following error codes: Engine: 452A, 4B1C A6CF DPF remaining distance 43.000km Gearshift and exhaust wobble a bit more so should and car has no power

(Translated from German)

CarlyMechanic

@CMario1007

I have a BMW 320d and it has the following error codes: Engine: 452A, 4B1C A6CF DPF remaining distance 43.000km Gearshift and exhaust wobble a bit more so should and car has no power

The error codes you've mentioned suggest issues with the Diesel Particulate Filter (DPF) regeneration frequency (452A) and the glow plug controller (4B1C). The DPF issue could be causing the lack of power and the exhaust wobble. The A6CF code is related to the radio. For the DPF, you might need to drive at a higher speed for a longer period to allow the DPF to regenerate. If this doesn't help, it might need a professional cleaning or replacement. The glow plug controller issue could be causing the starting problems and might need to be replaced. Please note that these are just suggestions based on the error codes. It's best to have a professional mechanic diagnose the car to confirm the issues and perform the necessary repairs. After you've had these issues addressed, could you please update us on the progress?

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