Alternator A/C voltage question

[Bmwe5320023.0]

No change at all in whining. I made sure no ground touched the plug on the amp.

Gotta be something else

[wpoll]

Does the amp output a "whine" with no inputs connected?

[Bmwe5320023.0]

No whine if rca cables are disconnected.
However there's whine if rca cables are only connected to the amp, not the headunit.
Latest theory is that rca cables function as antenna and pick up noise from possibly bad spark plugs and ignition coils, even though I have no misfires or codes.

[80stech]

Get some foil shielded cables with the shield grounded only on the source end (some will have arrows on them to direction) or make your own, or try the isolators you have in the picture.

[Bmwe5320023.0]

Do you have a link to the cables you recommend?

The isolators in my pictures, I already tried them. No change.

Got the plugs and boots today.

I guess I thought coils came together with boots, but I must've not realized this was not the case.

I replaced boots and spark plugs.

My old spark plugs were totally drenched it oil. Boots as well, and bottom of boots were kinda missing. Old plugs were gapped at 0.6 instead 0.4. I can't understand how this happened. I've replaced the cover valve gasket and spark plug gaskets as well before.

I guess I need to redo valve cover gasket to see what's going on there.

At this point I just wanted to see if the whine would go away.

Started the car, no luck. Whine is still there.

Withing 10-20 seconds the smoke filled my garage really bad, I turned off the car.

There must be a really bad leak that must've caused the oil burning with new spark plugs and boots.



I guess next step is to buy new coils and see if it helps. Obviously gotta redo the valve cover gasket. I'm pretty adamant I did it well a year ago, but the leaks on spark plugs are proof to the contrary.



What's the best brand for coils,
Delphi, nkg, brewing?
I can't find any coils by denso

[andrewwynn]

Do you have any plug in accessories? In my e53, I couldn't tune the radio when I had my USB plug in to charge my phone. The DC> DC power adapters are notoriously bad for creating radio interference or audible hum.

Make an audio recording or scan witg FFT program to figure out what is the frequency.

[Bmwe5320023.0]

Andrew my stock audio is completely removed, including wiring, amp, sub, oem HU, speakers, radio antenna on the trunk door, everything.

So it's a completely new installation where I connect to the headunit via Bluetooth

Can you tell me.mpre about scanning with FFT?
Never heard of it before

[X5chemist]

Mine has NGK and single tip Iridium plugs. A NGK coil set from Summit Racing goes for $140.99. #NGK-49177 After putting them in and running it, the range went above 500 miles! I think it maxed out at 525+ miles! So it did see a difference from old stock worn out coils. Three were original. Three were replacements. #3 was failing intermediately so I replaced them all.

[Bmwe5320023.0]

Nice results! Looks like NGK is still very reputable.
I think my Denso boots are good quality.
I just ordered Delphi ignition coils from rockauto, I read online that bmw changed their oem for coils from Bosch to Delphi due to issues with Bosch.
Will see if coils help with the whine...
Don't know if there's any difference in quality between Delphi, NGK and Bremi. I was gonna order Denso coils but realized Denso doesn't make coils, only boots

[Bmwe5320023.0]

New spark plugs, boots and coils didn't help with the whine.
Next idea is to try Newmar 150-A Alternator Line Noise Filter 150 Amp
Ordered it on June 1 from USA and still waiting.
I think it should be here in a couple of days finally.
Shipping to Canada takes longer than if i order on aliexpress lol!