125i N52 Cold Start Shaking

[olliedg6]

Hello there,

I recently bought myself an E82 125i coupe M sport. It's a 2010 with the N52 engine. Absolutely love the car and driving it.

However, I've noticed recently during the cold starts the car vibrates as if the engine is shaking it. It's not excessive but it's definitely noticeable. The rpm's also slightly fluctuate in the first 15 seconds of cold start before the engine settles into it's idle. I have uploaded a clip to youtube of this:

Having spent years researching this engine before I bought the car my immediate suspicion was something to do with VANOS solenoids, Coil Packs, Eccentric Shaft Sensor or CCV. I've heard there may also be a software update that fixes rough running.

A little background of the car. It's covered nearly 72000 miles. It drives beautifully, pulls like a train and doesn't have any hesitation when accelerating. The guy I bought it off hardly used it as he had another car. Looking at the MOT history in the last 3 years it's done an average of 1600 miles a year so wasn't sure whether the cold start issue is a result of it sitting. The last service was done in June of this year. It has had a coil pack replaced in 2022 so I wasn't sure if maybe the others need to be replaced as well. The car only smokes from the exhaust slightly on really cold starts but this only lasts a few seconds and haven't had to top up the oil at all yet so don't think it's CCV related.

I think my overall question is, is there an issue or am I being paranoid!

Thanks in advance!

Edit: No Engine Lights in the dash, I lost my OBD reader so can't pull any codes until I get a new one!

[mkeiser]

If you have access to INPA, try clearing adaptations...

[4JawChuck]

I would start with coils, I had to change mine at an earlier mileage than what you have now.

Have you received a misfire code?

[brake-fade]

Honestly, you're being paranoid. Lol! Just go have fun with it. I've owned one for 10 years, that sounds about right.

[olliedg6]

Thanks guys for all your replies. Cars booked in at a BMW specialist next month so will get them to look into it. For the moment the car seems to be driving fine its just the cold start annoying me but I'll live with it for the moment. Cheers for the help guys and I will update you when I take it in.

[olliedg6]

UPDATE:

Took the car in for a health check at a specialist. Turns out the air intake pipe after the maf was hanging loose and not secured to the rest of the manifold causing an air leak. This has now been fixed. The garage advised it might take a few days for the car's adaptations to adjust but first impressions the issue with the cold starts definitely seems better. The car also idles lower than it did before immediately after starting. Wouldn't say its 100% gone yet but I've got the car booked in for a full service next month with new spark plugs so hopefully fresh plugs will make it that bit smoother.

[olliedg6]

UPDATE:

So car seemed ok for last few weeks however as its started getting colder the shaking is back. When i put my hand on the engine cover, I can feel what i think is a slight misfire although it hasn't been enough to trigger any warning lights.

Also started having this noise today after a 20 min drive (see https://www.youtube.com/shorts/3Qbd-EWDYPI) I'm not sure how to describe it but it sounds like a faint cricket! Worried its the alternator belt/tensioner/pulley going out. I've got to drive about 220 miles tomorrow and having read up on horror stories of N series engines belts snapping and getting ingested into the crank seal I'm getting a bit worried. I know its like asking how longs a piece of string but how long roughly have I got before the belt goes? FYI the car is already booked in for next week for a full service including spark plugs as well as new alternator belt and tensioner so was hoping it would make it till then.