Sc400 drops to 11v under high load when stopped, stalls unless I raise idle.
#16
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If you have digital multimeter, check continuity and ohm between battery negative to chassis ground should b near 0.2 ohm. If it's good, now check how much voltage is coming out from behind the alternator( big wire that is held down with a nut) should see high 13v to low 14v.
If you see 13 to 14v, then your wires have too much resistance causing voltage drop.
If you don't see good charging voltage, you probably have faulty alternator.
Make sure you have no power steering leak which is right on top of alternator. It can cause alternator to short out.
Also what alternator are you running on the car??
I highly recommend denso if you are not using one already.
I have seen faulty alternator right out from the box many times.
Not a single bad one from denso.
Hope this helps.
If you see 13 to 14v, then your wires have too much resistance causing voltage drop.
If you don't see good charging voltage, you probably have faulty alternator.
Make sure you have no power steering leak which is right on top of alternator. It can cause alternator to short out.
Also what alternator are you running on the car??
I highly recommend denso if you are not using one already.
I have seen faulty alternator right out from the box many times.
Not a single bad one from denso.
Hope this helps.
Does that alternator diagnosis on wheels machine some shops have do a sufficient job or is the multimeter approach the only way?
Would a higher output alternator help this situation?
Who makes a reasonably priced unit that is also good quality?
#17
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Not sure about their quality, but you can buy high output alternators on eBay (I think stock SC400 alternators are about 140-150amps? While eBay has 200 amp alternators). Any battery/alternator shop should be able to build you an alternator with higher output as well.
#18
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
Not sure about their quality, but you can buy high output alternators on eBay (I think stock SC400 alternators are about 140-150amps? While eBay has 200 amp alternators). Any battery/alternator shop should be able to build you an alternator with higher output as well.
Thank you!
If anyone knows a good vendor, please let me know.
#19
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How do i raise my idle a bit?
I watched the voltmeter and tach like a hawk while pulling up to a stop light. If I shift in to neutral while pulling up to the light, the idle drops down to the first line below 1000 RPM. it is dead on top of the line blocking it totally. If i shift into drive with my foot on the brake, or pull up to the light in drive, the idle drops a tiny bit below the line. This is when the voltmeter goes into the red every time. It's like 1/8th inch below and enough to regularly send the meter into the red.
I don't think this is the only problem, but I think a slightly higher idle will sort this out at least in the short run. I ordered a high voltage alternator hoping this will do the trick.
Thank You!
I watched the voltmeter and tach like a hawk while pulling up to a stop light. If I shift in to neutral while pulling up to the light, the idle drops down to the first line below 1000 RPM. it is dead on top of the line blocking it totally. If i shift into drive with my foot on the brake, or pull up to the light in drive, the idle drops a tiny bit below the line. This is when the voltmeter goes into the red every time. It's like 1/8th inch below and enough to regularly send the meter into the red.
I don't think this is the only problem, but I think a slightly higher idle will sort this out at least in the short run. I ordered a high voltage alternator hoping this will do the trick.
Thank You!
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