BMW Z4: Multiple Issues Point to Faulty EGR Valve

Hey there! I had some experience with similar symptoms on my 2011 BMW 3-Series (I have some experience working on cars but nothing too fancy). My 335i was acting up just like yours, drop in power, smoking, and that annoying hissing. Definitely sounded like the EGR valve issue I dealt with. Took it to my workshop after trying to clean the EGR myself (wouldn't recommend that). They confirmed it was a jammed EGR valve, had to replace it completely. Cost me about 355 Euro, parts and labor included. The car's been running smooth since then, no more smoke or power issues. Before I can help more specifically, what's your mileage, and have you had any other recent repairs done? Also, is your check engine light showing any specific error codes? This would help narrow things down better. Can't stress enough how important it is to get this checked soon, it'll only get worse if you keep driving it like this.

Thanks for chiming in. My Z4 has around 22066 KM on the clock, and just had its regular service last month where they did the usual oil change and basic checks. Everything was fine then. Haven't pulled the error codes yet, to be honest. Planning to get that done this weekend. The symptoms only started about a week ago, and they're getting progressively worse. The hissing sound is particularly concerning, especially during acceleration. Good to know about your similar experience. Seems like a reasonable repair cost if it fixes all these issues. Did you notice improved fuel consumption after the EGR valve replacement? Mine's drinking fuel like crazy right now.

Hey again! Yeah, I remember helping you out with the EGR valve question. After seeing your mileage and hearing about the recent service, I'm even more convinced it's the EGR valve, just like what happened with my BMW. And to answer your question about fuel consumption, absolutely yes! After getting the new EGR valve, my fuel economy improved dramatically. Before the fix, my car was drinking fuel like it was going out of style, probably 25-30% more than normal. But once the new valve was in, it went right back to normal. It was actually one of the first things I noticed. Since you mentioned the hissing is getting worse, I'd definitely recommend getting those error codes checked ASAP. Don't wait too long, I learned that the hard way. When I ignored it initially, it started affecting other engine components. The sooner you get it sorted, the better. Quick tip though, when you get it fixed, make sure they clean the EGR passages too, not just replace the valve. My mechanic did that, and I think that's partly why I haven't had any issues since. Been about 18 months now, and she's running like a dream. Keep us posted on those error codes when you get them!

Thanks so much for all the advice! Yeah, I won't delay getting those error codes checked, planning to stop by the shop first thing this weekend. The fuel consumption thing is really hitting my wallet hard right now, so it's reassuring to hear that fixing the EGR valve sorted that out for you. Appreciate the tip about cleaning the EGR passages too, that's exactly the kind of insider knowledge I was hoping to get. I'll definitely mention that to the mechanic when I take it in. The cost seems reasonable for what needs to be done, especially if it solves all these issues. I'll update everyone once I get the codes read and know what's actually going on. Really hoping it's just the EGR valve and nothing more serious. Thanks again for sharing your experience, it's been super helpful and definitely made me feel better about the whole situation!

My Mini Cooper 1.6d 110hp won't start, battery is ok, diesel is ok, I don't understand.

(Translated from French)

Start by checking the basics: ensure the battery connections are clean and tight. Next, listen for any clicking sounds when you turn the key, which could indicate a starter motor issue. If the starter seems fine, inspect the fuel system for any leaks or blockages. If these checks don't reveal the problem, it might be worth checking the glow plugs or the ignition system. Let me know how these checks go or if you have any further questions!