[AllydNYC]

So I've done a fair share of searching and either have come up with vague answers or they are related towards N54 engines. I just got out of warranty one month ago and assuming I still had one I'm sure they would bs and say nothing is wrong.

I have the car since new, 4 years and 1 month old with 31k miles on it. I use Shell 91 (no 93 here ) and have been for quite sometime and been going to the same gas station. Stock engine components and clean air filter... I DID have a AFE intake in it about 1.5k miles ago that started to get an air leak so I'm assuming the MAF sensor could have gotten dirty but don't think it would lead to this... more of a rough engine idle I would think.

Anyway it's simple. I've NEVER had this issue before and has happened twice in the last 2 weeks and I only drive the car twice a week. It's about 95 out. When coming to a stop the engine idles at 800 instead of 600. I don't usually use the A/C but I did today and it idled at 800 RPMs for a while (should be at I think ~650-750 with A/C? ), this is after 30 miles of driving. Turned off the A/C and still 800 RPMs. I've driven 30 miles last week with NO climate control on the whole ride and the engine idled at 800 RPMs when getting off the highway and the couple mile drive to the garage. The car doesn't do anything weird beyond this but it's a big concern of mine. I've turned off the car and back on and still idles like that. If I leave the car overnight it idles correctly. I've checked the intake clamps even though that would probably cause other issues if loose, they were tight.

Sorry for it being lengthy, I rather give all the information in the 1st post. If anyone has insight on this or has the same 'problem' I would like to know.

[RupertPupkin]

Cars fine. You're being anal

[AlanAZ]

Mine definitely idles higher with the A/C on. Maybe not 800, but ~750. Makes sense, as BMW designs it's engines to conserve fuel, with the A/C load, it will need to idle higher to compensate.

btw, it's better for the A/C to use it a regular basis, this keeps the seals lubricated and prevent them from drying out/failing, and lubricates the compressor. Google for more info.

Cleaning the MAF is easy to do, and a good idea if you suspect you had an air leak.

[AllydNYC]

Originally Posted by RupertPupkin

Cars fine. You're being anal

It's a high possibility but I've never seen this happen before until the last two weeks. With all due respect I would like to know why it started doing this. Other threads haven't come to an answer either.

Originally Posted by AlanAZ

Mine definitely idles higher with the A/C on. Maybe not 800, but ~750. Makes sense, as BMW designs it's engines to conserve fuel, with the A/C load, it will need to idle higher to compensate.

btw, it's better for the A/C to use it a regular basis, this keeps the seals lubricated and prevent them from drying out/failing, and lubricates the compressor. Google for more info.

Cleaning the MAF is easy to do, and a good idea if you suspect you had an air leak.

I didn't know about the whole seal thing... will run it a bit more. It's just strange the car idles so high when A/C was not on.

[Onefreakinuserid]

Car is fine. Cars run richer in hot temps in an effort to help cool engine.

[RupertPupkin]

Every car will increase its idle speed when the AC compressor is on and will adjust idle RPM for other variables as well.

Originally Posted by AllydNYC

It's a high possibility but I've never seen this happen before until the last two weeks. With all due respect I would like to know why it started doing this. Other threads haven't come to an answer either.



I didn't know about the whole seal thing... will run it a bit more. It's just strange the car idles so high when A/C was not on.

[AllydNYC]

Originally Posted by RupertPupkin

Every car will increase its idle speed when the AC compressor is on and will adjust idle RPM for other variables as well.

Hey but I've taken trips with the A/C off the entire trip and it still happens. I guess it's those 'other variables' causing it to idle higher for the first time ever in it's life.

[Johnny D]

Does it idle rough or inconsistent?

Most cars have an ICV Valve (Idle Control Valve). Id start my search there.

[BoogeyMan'sBMW]

had a similar problem

http://www.e90post.com/forums/showthread.php?t=606459

idk if some of the other details are the same but using Techron Concentrate Plus fixed the problem