benhahn1
BMW Z3 Rough Idle & Stalling, IAC Valve Issue?
Check engine light on
Fault stored
Stalling while idling
4 comment(s)
Thanks for sharing your experience! Mine's at 106739 KM and had its last service about 4 months ago. The problem's definitely worse when the engine is cold, and yeah, I've noticed I'm filling up more often lately. My fuel consumption has gone up by about 15-20% I'd say. You might be onto something with the intake contamination, I'll get that checked out before replacing the idle control valve. Would save me some cash if it's just a cleaning job rather than a parts replacement. Appreciate the tip!
Hey again! Wow, those details you shared about your Z3 really ring a bell. My Z4 was showing almost identical symptoms at around 110,000 KM. That increased fuel consumption you mentioned, about 15-20%, was exactly what I experienced too. It's like déjà vu! After what I learned from my experience, I'd definitely recommend getting that intake system checked first. In my case, once they cleaned out all that gunk, not only did the idle smooth out, but my fuel economy went back to normal too. The timing of your symptoms (worse when cold) matches what I dealt with perfectly. Quick tip from my experience, ask your mechanic to check the throttle body while they're at it. When they were cleaning my intake, they found the throttle body was pretty grimy too. Getting both cleaned at the same time saved me some labor costs in the long run. Just be careful with using those over-the-counter intake cleaners if you're thinking about it. I tried that first and it didn't do much. Professional cleaning made all the difference. Keep me posted on what you find out!
Thanks so much for the detailed follow-up! That's really helpful about the throttle body too, definitely makes sense to get both checked while they're in there. I've actually already booked it in with my mechanic for next week, and I specifically mentioned the intake system and throttle body cleaning based on your advice. You've probably saved me from unnecessarily replacing the idle control valve! Funny how similar our situations are with the mileage and symptoms. I was tempted to try those intake cleaners from the auto store, so I'm glad you warned me about that. Will definitely stick to getting it professionally cleaned instead. I'll keep you updated once I get it back from the shop. Really appreciate all your help and for sharing your experience, it's made me feel a lot more confident about what might be wrong with my Z3!
Hey there! I've got some experience with BMWs (some experience with maintenance and repairs). Had a similar issue with my 2002 BMW Z4 last year, and my 325i before that. Those symptoms sound exactly like what I went through, rough idle, stalling, unstable RPMs. Took it to my trusted workshop and it turned out the intake was heavily contaminated, causing irregular airflow. The full cleaning service cost me 425 Euro, but it fixed the problem completely. The mechanic showed me how gunked up everything was, pretty shocking actually! Before you jump to conclusions about the idle control valve though, could you share more details about your Z3? Like when was the last time you had a thorough service, and does it happen more when the engine's cold or warm? Also, have you noticed any drop in fuel efficiency? These details would help me give you more specific advice based on my experience.