Cold start issues

[gigidabrunda]

Originally Posted by tlow98

I am posting this here for anyone that finds it. I solved my cold start stumble very easily.

2014 XDrive 35i

I unplugged the MAF on a cold engine and gave it one complete warm-up and drive cycle with the MAF unplugged (it ran fine and no check engine light came on). Then I plugged the MAF back in and allowed the motor to go back to completely cold before turning it on again.

The issue has not returned for 1 month of daily starts. Previously, it was stumbling and running rough on every single cold start for 5 months. I was dreading the injector replacement or taking it back to the dealer for coding. Neither was necessary.

I can't explain it, but I saw it posted a couple of other places and it also worked for me. I'm assuming it resets some adaptions.

Anyway, hope this helps someone!

I have the same exact problem on my 228i and will try to unplug MAF and go through the cycle.

I can also reset adaptations (MAF, Idle, Lambda) from MHD App but after I put car under WOT the next cold start is awful.

[X Driver]

Originally Posted by 640ijims

Occams Razor…even if vehicle in question is modded, the simplest solution attempt to remedy problem is Chevron Techron Complete Fuel System Cleaner. One 20 oz can to a fill up and then another back to back treatment. Air /spark/ fuel equals combustion…when I get stupid and use non top tier fuel, the problem usually reads its ugly head…Techron seems to cure it

Try this, worked out for me.

[S65B40YYC]

Originally Posted by ciscorob

I have this exact same issue, albeit my wife's X5 is a 2016 and not an M model, just an sDrive. It does not happen all the time, it happened once for me and just this morning to my wife. I haven't checked for any stored codes. I've put in new plugs (from BMW) new air filter, (doing another oil change this week), and each of the pulled plugs showed no issues in regards to lean or rich in any one individual cylinder. The car is stock, no mods.

Has anyone discovered what this could be? I'll be digging through the car to see if I spot anything noticeable and report back, but if you've found something I'd love to know

I have also been having this exact issue and I'm stage 1 BM3 with stock DP's. No codes or anything. I did have a random O2 sensor code about 5 tanks ago which never came back.

There does not seem to be a definitive solution in this thread, anyone have an update on this situation? One poster claimed BMW replaced all MAF, plugs, coils and injector's and the problem persists. Another poster is saying techron is the solution and others say no.

Any updates??