2015 Volvo V40 Diesel Engine Distress: Check Engine Light, Power Loss, Unsteady Engine and Possible Crankshaft/Camshaft Sync Issues

Hey! I can definitely sympathise with your situation. Funny enough, I had a kind of similar issue with my 2018 Volvo XC60 Diesel not too long ago. Like yours, mine exhibited some real puzzling symptoms: stalling, rough idle, and an on-and-off engine light, among other things. Didn't spot any metal bits, but goodness, the starter issue was a pain. After several sleepless nights, I decided to drag her down to the garage. Sure enough, the diagnosis came back as a defective crankshaft sensor. That's right, it had been causing all the ruckus! Those symptoms you described sounded pretty familiar to what went down with my car. Apparently, the crankshaft sensor's job is to monitor the engine's speed and rotation. A faulty one can seriously mess up the engine timing, causing the odd symptoms. Don't sweat too much though, the problem, though serious, is pretty common. The mechanic just replaced the faulty sensor, and the car's been running smooth as glass ever since. No more weird noises, no more power loss, and certainly no more pesky check engine lights. Make sure to have it checked out sooner rather than later. Hope that helps a bit, and good luck with your ride!

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Hey, thanks for the info! It's a relief to hear that your car is all good now after changing the crankshaft sensor, because those symptoms are exactly what I'm getting with my V40. Now, I hate to push the issue further, but do you remember roughly how much it set you back to have that sensor replaced? Just so I know what ballpark I'm in before I start chatting with mechanics. Also, has anything else cropped up since or has it been smooth sailing now? Thanks again for your help!

(Translated from German)

Hey there! No worries about pushing the issue, it's good to be well-informed when it comes to your motor. When I had my crankshaft sensor fixed, it set me back about 250€. Not cheap I know, but totally worth it in my book. The crankshaft to camshaft position was incorrect when I first went in, but I'm pleased to say the mechanic did a top-notch job of sorting it out. Car’s been purring like a kitten since! No other surprises have come up either - smooth sailing all the way from there. Cheers and all the best with your V40!

(Translated from German)

Thank you! Your insight has been invaluable. I’m bracing myself for that €250-ish hit, but getting my V40 fixed and back on the road is a top priority for me. Besides, the peace of mind knowing the car is working fine, no other hidden surprises or concerns, is worth a few hundred Euro. I'm going to ring up a mechanic first thing tomorrow and hopefully put this whole fuss behind me. Thanks again for putting my mind at ease. Safe and smooth driving to you!

(Translated from German)