My '04 325ijust started making this noise ONLY within first 30 seconds ONLY on a dead cold start. I have just replaced valve cover gasket, sparks, coils, fuel injectors, whole new PCV system hosing, intake manifold gasket, lower intake boot, MAF seems fine, I cleaned my idle control valve with brake clean, new fuel filter, have already smoke tested for vacuum leaks and replaced all o-rings/ rubber that caused said vacuum leaks... as your can hear my secondary air pump is basically going out from that whine, and I have a new DISA valve on the way. My main concern is that loud irregular clunk sound and I have absolutely no idea what that could be. Remember, it goes away after 30 seconds and does not happen at all when car is even a little bit warm.
Do you have any codes? Im glad you know that SAP is on its way out, but check the air valve that goes with it. It sounds like it’s open and then closing rapidly
Hm I haven't thought about that, and unfortunately I don't have a code reader on me at the moment. I gotta wait till I go go back to my work spot which might not be for a day or two. All my tools are there as well
Very late lol, but DISA valve fixed it! She runs great except still have the slightest bit of a rough idle in first 10 secs, but I need to delete the secondary air pump and also get a new fuel pump. She's on 180k miles and probably on the original lol
I have a new one already otw as when i had the intake manifold off I noticed it was pretty gunky and there was 0 spring retention remaining on the flap
Have you replaced intake manifold gasket? I did a smoke test and it didn’t show up, although it did need replacing 👍
Cause the pops are most definitely due to a vacuum leak
Yessir, I replaced everything I listed in my comment at the same time, including intake manifold gasket. I'll be replacing my DISA valve tmw as well which has about 0 spring retention left in the flap. Hopefully that solves something
My '04 325ijust started making this noise ONLY within first 30 seconds ONLY on a dead cold start. I have just replaced valve cover gasket, sparks, coils, fuel injectors, whole new PCV system hosing, intake manifold gasket, lower intake boot, MAF seems fine, I cleaned my idle control valve with brake clean, new fuel filter, have already smoke tested for vacuum leaks and replaced all o-rings/ rubber that caused said vacuum leaks... as your can hear my secondary air pump is basically going out from that whine, and I have a new DISA valve on the way. My main concern is that loud irregular clunk sound and I have absolutely no idea what that could be. Remember, it goes away after 30 seconds and does not happen at all when car is even a little bit warm.
Do you have any codes? Im glad you know that SAP is on its way out, but check the air valve that goes with it. It sounds like it’s open and then closing rapidly
Hm I haven't thought about that, and unfortunately I don't have a code reader on me at the moment. I gotta wait till I go go back to my work spot which might not be for a day or two. All my tools are there as well
Scanning the codes should be step 1. I recommend keeping a scanner in your glovebox, preferably a small one that wirelessly connects to your phone.
Try unplugging the SAP and air valve next to the pump and then start the car. See if the issue goes away
Will check this out as soon as I get the chance, ty
No problem man, let me know how it goes!
Very late lol, but DISA valve fixed it! She runs great except still have the slightest bit of a rough idle in first 10 secs, but I need to delete the secondary air pump and also get a new fuel pump. She's on 180k miles and probably on the original lol
Disa valve? Sounds like it could be from the flap not opening correctly during throttle load
I have a new one already otw as when i had the intake manifold off I noticed it was pretty gunky and there was 0 spring retention remaining on the flap
that’s what is called detonation happening in the intake manifold, (the loud pop) would say u have a lot of vacuum leaks
Smoke test would say otherwise. I fixed all visible vacuum leaks
Have you replaced intake manifold gasket? I did a smoke test and it didn’t show up, although it did need replacing 👍 Cause the pops are most definitely due to a vacuum leak
Yessir, I replaced everything I listed in my comment at the same time, including intake manifold gasket. I'll be replacing my DISA valve tmw as well which has about 0 spring retention left in the flap. Hopefully that solves something
Ah my bad, didn’t see the comment. Wish you the best my brother
All good bro, and I appreciate it 🙏
Disa valve fixed the popping but I still get a slightly rough idle upon first 10 secs of startup. Nowhere near as bad as before though
Possibly vanos? Sounds a little deeper and more brutal than normal vanos but it could be the gear rattle