I have had two different Alt on my 3.0 and so far both have had to be rev'd to 3,500 rpm to get them to turn on. No voltage out put when first started, once rev'd to 3.5k they are fine and put out great voltage. I have replaced the main wire to the alt, the negative battery wire (this is on a milano) cleaned my grounds. I bought the second alt because I thought the first one was the cause of this. I guess the Alt is grounded through it's body and thus the engine, the battery ground is bolted to the PS bracket just above the Alt, but I have been told to run I wire from the alt bracket to the PS bracket just to make sure.
Any ideas?
Sam,I reckon so...
My 535i had an ABS light coming on lately,after say 20 to 100 km.I went thru the ABS system and nothing...
Then one day had to jump start the Giulietta and used the BMW..But I could not hear the alternator whining as it normaly does when charging a flat batt.
Reved the Bimmer up past 3000rpm and suddenly heard the familiar whine ....I then knew the reg had gone,replaced it and my ABS problem also fixed itself..Abs light will come on with low batt. voltage..
The Bimmers an auto,hence the low revs ....
Id still go with reg..
My 535i had an ABS light coming on lately,after say 20 to 100 km.I went thru the ABS system and nothing...
Then one day had to jump start the Giulietta and used the BMW..But I could not hear the alternator whining as it normaly does when charging a flat batt.
Reved the Bimmer up past 3000rpm and suddenly heard the familiar whine ....I then knew the reg had gone,replaced it and my ABS problem also fixed itself..Abs light will come on with low batt. voltage..
The Bimmers an auto,hence the low revs ....
Id still go with reg..
Mmmmmm,great advice there..
Sam,Have you put 12v directly from batt.through a 12v low wattage globe to the alternator yet?
This is the simplest and most direct way of checking the excitment circuit.
Do this first and report,ok?
Stupid question,you have the green wire connected to the correct terminal on the alt.?There are 2,1x green wire,1x capacitor for noise..
Barry
Sam,Have you put 12v directly from batt.through a 12v low wattage globe to the alternator yet?
This is the simplest and most direct way of checking the excitment circuit.
Do this first and report,ok?
Stupid question,you have the green wire connected to the correct terminal on the alt.?There are 2,1x green wire,1x capacitor for noise..
Barry
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grantleyrich
- Silver
- Posts: 22
- Joined: Fri Jan 28, 2005 5:02 am
- Location: Surrey, UK
Hmmm.... I have exactly the same problem with my car, again with two separate alternators. I need to spin the motor up to 3000rpm to get the alternator to wake up and start cahrging, after which it is fine right down to idle speed. I have checked the voltage output from the alternator and the warning light is accurate- or esle the light and meter are both as inaccurate as each other.
In my case, the warning light also glows faintly when the heater fan is on. I haven't been able to check if this is just reflection from the orange heater fan warning light, but it worries me slightly when it gets worse with the wipers on as well.
I was planning to hook up a voltmenter to the battery and check voltage readings to see if I was suffering from loss of charge due to aged wiring or poor earths. New main cables and another thorough clean of earth connections are high on the list of jobs to do to try to crack this. This post has got me thinking that while this might help it may not be the answer.
Interestingly, I used to have a problem with indicators that is much better now that I have new sills. I wonder if there is some merit in fitting an earth strap from the engine bay to the battery lead direct rather than relying on the conductivity of rust in the bodyshell? Or am I way off track with this?
Grant Richardson
displaced Kiwi
In my case, the warning light also glows faintly when the heater fan is on. I haven't been able to check if this is just reflection from the orange heater fan warning light, but it worries me slightly when it gets worse with the wipers on as well.
I was planning to hook up a voltmenter to the battery and check voltage readings to see if I was suffering from loss of charge due to aged wiring or poor earths. New main cables and another thorough clean of earth connections are high on the list of jobs to do to try to crack this. This post has got me thinking that while this might help it may not be the answer.
Interestingly, I used to have a problem with indicators that is much better now that I have new sills. I wonder if there is some merit in fitting an earth strap from the engine bay to the battery lead direct rather than relying on the conductivity of rust in the bodyshell? Or am I way off track with this?
Grant Richardson
displaced Kiwi
Yep, once it hit 3500 rpm it is fine even at idle, I am not using my battery light, I am using a volt meter to test this, I do have a wire run from the batter to the junction box. The problem is that I have to rev to 3500 to get the engine to run right also since I have GoTech installed, the low volts really mess's with the injection system, stumbles bad until I get the alt to kick on. If it were less than 2k it would not bother me so much, just don't like to dry rev a cold engine at every start up.
Sam,
Last year I installed a 164 alternator in my 86 GTV6 and in doing so I partially resolved this issue.Previously the car had to be wound up to about 2000 rpm to get the alternator to charge.Now I can kick it in at about 1400 rpm.At the time I tried to research this issue but due to the illegible GTV6 wiring diagrams I had to work with (Cardisc) all I could do was determine that the problem originates in the excitation circuit for the alternator.This circuit runs through the dash warning light and according to a post I found on the old forum can also involve some other components depending on the year of production.
http://www.alfagtv6.com/discus/messages ... m#POST4927
Last year I installed a 164 alternator in my 86 GTV6 and in doing so I partially resolved this issue.Previously the car had to be wound up to about 2000 rpm to get the alternator to charge.Now I can kick it in at about 1400 rpm.At the time I tried to research this issue but due to the illegible GTV6 wiring diagrams I had to work with (Cardisc) all I could do was determine that the problem originates in the excitation circuit for the alternator.This circuit runs through the dash warning light and according to a post I found on the old forum can also involve some other components depending on the year of production.
http://www.alfagtv6.com/discus/messages ... m#POST4927
1986-GTV6
1989-75 Twinspark very sadly sold-remarkable sedan !
2014 Audi Q5 3.0l TDI - torque MONSTER
1989-75 Twinspark very sadly sold-remarkable sedan !
2014 Audi Q5 3.0l TDI - torque MONSTER
I have felt so bad for giving you the duff gen at the start that I felt we had to make this a group thing and resolve your problem..Good stuff!! Im chuffed you getting to the bottom of this..