128i engine stumbles???

[Swimjim]

thanks for all the info everyone. i am the 2nd owner. picked up the car in 10/2010 with less than 25k miles on it and nearly fully loaded - convenience/winter/sport pkg's. the only thing missing is the HiD lights!!!

the car is scheduled to get a 60k mile check up in a couple weeks - i will mention to the dealer. but the rare drop of the rpm has only happened when the a/c is on. the car is an automatic.

having the a/c really draws down on the power of the engine. other than that, the car is absolutely fun to drive around town and is great on long trips.

thanks again

[Zeros and ones]

Originally Posted by Stupenal

http://www.1addicts.com/forums/showthread.php?t=844863

Copy pasta of the steps:

1. Updated vehicle software.
2. Swapped 6 new ignition coils
3. Inspected spark plugs
4. Replaced eccentric shaft sensor
5. Smoke tested intake for leaks
6. Checked vanos function
7. Checked fuel pressure
8. Tested sample of gasoline and found no water/contaminants
9. Performed ethanol test and found 5% (????)
10. Filled injection flush container with fresh gas and ran through fuel rail
11. Installed 6 new spark plugs
12. Swapped injectors from known good car
13. Checked crankcase ventilation pressure
14. Increased idle speed
15. Performed compression and leakdown test (all cyl within range and good psi and within spec, good to know!)
16. Compared dme status requests to known good car
17. Unplugged MAF sensor
18. Checked cam timing
19. Swapped pre cat 02 sensors from known good car
20. Submitted PUMA case to BMWNA and instructed to try swapping post cat o2 sensors
21. Instructed to replace eccentric shaft.
22. Vehicle operating as designed at this time.

Car was at the dealership for 3 days as they went through these steps, and I got a lovely f30 328i non sport loaner. Slightly off topic, but mini rant - I first drove the f30 328i during BMWs annual test drive our car against our competitors event right at the f30s launch time. I found the car lacking in interior quality, steering feel, handling, and overall dimensions. I found the 2013 Lexus is250 (2nd generation, not even the newest generation) to be nicer in interior quality, which is amazing when I look back on it now and after sitting in the 2014 3rd gen is250 (absolutely amazing interior). I figured maybe this test drive of the f30 was just a short anomaly, and maybe the car isn't as bad as I thought. After having the f30 for 3 days, I'm even more disgusted at how BMW has evolved into its current state. The car drives like a nicer accord (girlfriend has one), and has no soul whatsoever. It can grip the road decently, but you don't have any feel or sensation and the larger dimensions are really felt. I can understand why people rave about the n20 because of its power and torque plus fuel efficiency, but it sounds terrible and other gimmicks like auto start/stop (yeah i know u can turn it off) just make it worse. /End rant.

thank you sir. Going to go to my dealer with this info and see what they can do.

[Pyrat 2]

Originally Posted by Swimjim

On, I believe

Could be simply ac cycling. I would do the following:
Check for codes. You can either buy a cheap obd device on amazon or simply go to autozone and have them read any codes. Doesn't cost anything.
If nothing is found I would try the injector cleaner. Either full techron or BMW cleaner.
Still if no luck replace the plugs if they haven't been replaced yet. I replaced mine at about 60k on my n52 330i and it made a huge difference. No stumbling and my mpg went up by about 1.5.

[TheSt|G]

Originally Posted by Stupenal

Car was at the dealership for 3 days as they went through these steps, and I got a lovely f30 328i non sport loaner. Slightly off topic, but mini rant - I first drove the f30 328i during BMWs annual test drive our car against our competitors event right at the f30s launch time. I found the car lacking in interior quality, steering feel, handling, and overall dimensions. I found the 2013 Lexus is250 (2nd generation, not even the newest generation) to be nicer in interior quality, which is amazing when I look back on it now and after sitting in the 2014 3rd gen is250 (absolutely amazing interior). I figured maybe this test drive of the f30 was just a short anomaly, and maybe the car isn't as bad as I thought. After having the f30 for 3 days, I'm even more disgusted at how BMW has evolved into its current state. The car drives like a nicer accord (girlfriend has one), and has no soul whatsoever. It can grip the road decently, but you don't have any feel or sensation and the larger dimensions are really felt. I can understand why people rave about the n20 because of its power and torque plus fuel efficiency, but it sounds terrible and other gimmicks like auto start/stop (yeah i know u can turn it off) just make it worse. /End rant.

Spot on, BMW died with the E82 going out of production.

Originally Posted by HeelToe

Could be simply ac cycling. I would do the following:
Check for codes. You can either buy a cheap obd device on amazon or simply go to autozone and have them read any codes. Doesn't cost anything.
If nothing is found I would try the injector cleaner. Either full techron or BMW cleaner.
Still if no luck replace the plugs if they haven't been replaced yet. I replaced mine at about 60k on my n52 330i and it made a huge difference. No stumbling and my mpg went up by about 1.5.

It is the AC cycling.

Generic OBD code reader is pretty useless as we have many BMW specific codes. Get one made for BMWs.

[toronto128]

I had the same problem on my 2013. it would idle just over 600rpm, and sometimes dip below that, feeling as though it was borderline going to stall. I complained about it at the dealer, they claimed they couldn't do anything about it. Though when I got the car back, the idle was just over 700rpm, and i never had the issue again.

this is warm idle, ac off