BMW Z4 Stalling and Jerking: Fix Your Misfiring Engine

Had similar issues with my 2019 BMW M240i last month. Started with rough idle and jerking during acceleration, exactly like yours. Turned out two ignition coils were failing and one spark plug was completely worn. The garage found the connection at the ignition coil pack was loose and corroded, causing misfires. They had to replace both coils and all spark plugs just to be safe. Not a super serious repair if caught early, but ignoring it could damage the catalytic converter eventually. The job was straightforward, took about an hour once they diagnosed it. I'd say any competent BMW specialist could handle this, doesn't have to be the dealer. Just make sure they use OEM parts for the ignition system. Check your service history, if those are original coils and plugs at 157k km, they're definitely due for replacement anyway. Your symptoms are textbook ignition system problems.

Thanks so much for sharing your experience, sounds exactly like what I'm dealing with! Looks like I need to bite the bullet and get those coils and plugs replaced. Just curious, do you remember roughly how much you ended up paying for the whole job? And has everything been running smoothly since the repair, or have you noticed any other issues pop up? Really appreciate the help!

Hey there! Following up on my earlier post, yep, got it all sorted out and my car's running like a dream now! The mechanic confirmed it was indeed a faulty ignition coil, just as I suspected. They found a dodgy cable connection that was causing all the drama. The final bill came to 95 € for fixing the cable connection and replacing the defective parts. Way cheaper than I initially feared! Since the repair, my M240i's been performing perfectly, no more rough idling, stalling, or that annoying jerking during acceleration. It's like having a completely different car. Honestly, it was such a relief to get it fixed. These BMW engines are pretty solid once you sort out the ignition system issues. Just make sure you get a qualified mechanic who knows their way around these engines, they're not your average machines! If you're still on the fence about getting yours checked out, I'd say go for it. The peace of mind is totally worth it, and it's better to fix it now before it potentially causes bigger problems down the road.

Just got back from the mechanic and wanted to update you all! Finally took my Z4 in last week. Talk about timing, turns out three of my ignition coils were shot and two spark plugs were totally worn out. The mechanic found some corrosion in the connections too, which explained the weird behavior. The repair was surprisingly quick and affordable. They got everything sorted in about 90 minutes, and the total came to less than I expected. Grabbed some coffee while I waited, and before I knew it, the car was ready to go. You should see how it runs now, smooth as butter! No more stalling, no jerking, and that annoying check engine light is finally off. It's honestly like driving a different car. Really glad I didn't put this off any longer. Thanks again for pushing me to get it checked out. Sometimes you just need that extra nudge to do the right thing. Definitely learned my lesson about regular maintenance this time around!