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mike

engine-speed dependent whine on AM radio band...

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OK all you electronics experts--is it the alternator or the ignition?

I'm running resistor plugs and the OEM spark plug terminals (with their built-in resistors)...what else do I do?

If it's the alternator, how to I fix?

There's a really good 50s & 60s oldies AM station in Cincy and I can't pick it up at all in the 02, but can in the E30...

TIA

mike

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I know the electronic ignition modules can cause a whine. Do you have one and if so, where is it mounted? How long is your radio ground and where is it grounded? What positive lead are you using for the radio. What kind of vondition is the antenna cable in?

As for the alternator, do you have the ground from the alt to the head?

Cris

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Right - that'a fairly easy fix. Radio Shak or any stereo supply store can give you a capacitor, which they'll brand as some sort of "noise suppressor" (so that they can mark it up a ton). Also agree with checking your grounds; you have someting looping somewhere.

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1. alternator is properly grounded with its very own brown ground wire per factory.

2. radio is grounded to the classic heater mounting bolt--ground is about 7 inches long

3. radio is wired thru the ignition switch to the proper wire for radio installation per the manual

4. My electronic ignition is a Delta Mk 10B CD system, and the whine persists with it turned off.

5. Antenna is fine--pulls in faint FM stations that wouldn't be audible if it were disconnected or bad (know this from experience)

If it is indeed the alternator as Curt states, which alternator terminal do I attach the capacator to?

TIA

mike

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Not frequency or wavelength dependent, it has more to do with timing.

50's & 60's music is too early for the 02 to pick up.

If it were later 60's through the mid 70's, you would have no issues at all.

You DO have the hood grounding strap installed?

(doesn't do much, just thought I'd annoy you with it)

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of all places:

"Connect the suppressor condensor to the regulator." and

"Connect the suppressor condensor to the alternator terminal B+.",

both from page 65-11/4.

Page 12-32/1 shows two different regulators. The one with yellow tape is "not-suppressed"; the one with white tape is "suppressed".

I suspect the condensor at the alternator B+ terminal is the one that will kill an engine speed dependent whine. If you get an aftermarket one, attach it to the back of the alternator.

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From a current for sale ad:

http://www.bmw2002faq.com/component/option,com_forum/Itemid,50/page,viewtopic/t,279740/

The first picture shows the back of an alternator which has the condensor attached at about the "4PM" position; see the little black rectangle.

Unfortunately, this is an alternator with internal regulator, so the terminal hookup won't help if you have an external regulator alternator, but at least you can see what the condensor looks like!

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LOL - I like that answer.

There is another 2-step process to fix Mike's problem:

1) remove radio

2) rev & enjoy

;)

Karl

3 02s & no radios

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