[vtms]

Originally Posted by Oliv

I suppose it's quite hot in Phoenix now ? Check the air/water intercooler, it's known to develop leaks on the S55...
When it does your intake temperature goes to the roof which can cause what you describe, and you're not always warned by a CEL

It sure is hot, but this is the second summer here with my M2 and never had a problem during the previous summer. It only happened after the recent oil change. How would I check the air/water intercooler?

[vtms]

Originally Posted by doughboy

Have you got access to a fault reader? Lots of minor faults won't triggger CEL but might indicate an issue.

Maybe the dealer checked that, did they confirm?

Is it sluggish from cold, or just when hot?

They actually never checked it with any equipment, just a mechanic test drove it with me to see if anything was obviously wrong, but he didn't know how the car drove before so it was kind of pointless. I don't have a fault reader, except one provided by my car insurance and it doesn't show any errors. The engine is sluggish from cold and hot as far as can tell. So weird. I still think they reset something maybe by accident at the dealership during oil change, but won't tell me.

[Oliv]

Originally Posted by vtms

It sure is hot, but this is the second summer here with my M2 and never had a problem during the previous summer. It only happened after the recent oil change. How would I check the air/water intercooler?

https://f80.bimmerpost.com/forums/sh...3&postcount=24

check the level in the coolant tank pictured above
Not very common on a nearly new car but - hey - it's a 30 seconds check

[doughboy]

Doubt it's the intecooler water level. I drove mine empty and it made no difference to performance at all unless you drove it hard and the engine was hot.

No warnings either unless the intake temp was too high.