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Discussion Starter · #1 ·
My battery light, bulb tailight indicator and basically all the lights that come on when you first turn the key on all come on NOT under wide open throttle, but say if I let off the throttle to around 60-70% or so during a pull. You can definately feel the hesitation when the lights come on and right after they go off everything is fine...you can stay into the throttle at that point and be ok. This all happens in a split second at around 7,000rpm-7,500rpm.

I am not sure if this has something to do with just a throttle angle change that makes all the lights on my dash come on, or what? I did have quite a bit of coolant get on my alternator, so I am getting some electrical cleaner tonight and try that out to see if it cures the issue or not.

An interesting piece of information is my battery voltage on my logs from the AEM show 15.8v and that voltage changes coincidentally right when I let off the throttle say around 20% or so. Meaning that if I was at 90% throttle I could go down to around 70% throttle and the battery voltage would jump from 13.x V to 15.8 and that is when the dash lights come on and the car hesitates which all happens in a split second. The voltage will go back down to normal if I am off the throttle for a bit.

I am just really curious if anyone ever had anything like this happen before and if so, what was the cause of it?



Thanks
 

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Discussion Starter · #2 ·
I tried the electrical cleaner on the alternator and the car was fine the first couple of times, but the car did flash the dash lights after I got on it about the 3rd time and the battery voltage went to 15V+ again like every other time it happens. Not sure what the voltage spike is all about.

Not really sure what exactly the problem is at this point.
 

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never had that happen but sometimes the odo flashes under wot :wtflol:
 

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Could be the voltage regulator in the alternator going out and overcharging the system. Change it quick before it starts burning up components!
 

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I don't have an answer, but maybe I can help spark some additional replies.

Just to make sure I'm clear, you're saying that your lights shut off when you're NOT under WOT - but are perfectly fine when at full throttle?

If there's an increase in voltage AND a loss of power at the same time, would some electrical component in the car shutting off temporarily cause this?
 

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Discussion Starter · #6 ·
Un4GvnLude said:
I don't have an answer, but maybe I can help spark some additional replies.

Just to make sure I'm clear, you're saying that your lights shut off when you're NOT under WOT - but are perfectly fine when at full throttle?

If there's an increase in voltage AND a loss of power at the same time, would some electrical component in the car shutting off temporarily cause this?
Correct.

All the dash lights do NOT come on when I am at WOT rather they do come on if I let off the throttle a little bit during mid run.

For example:

If I am at WOT everything is pulling hard and strong and then for some reason subconciously I think I need to let off a little bit (might have been losing traction slightly or whatever), so I proceed to let off the throttle to around 70% or so and at that time the rpm's are around 7000 and the dash lights come on and the car immediately hesitates. The dash lights only stay on for a split second and then go back off quickly. I can stay into it and be fine as long as the dash lights do not turn on.

FYI: I know the throttle position that I am at, voltages, boost, etc by the log I am pulling out of the ECU, so I am not just guessing what the voltage was and what the throttle position was, etc.

I would guess that there are things shutting off in the car...it almost looks like the ignition completely shuts off for a split second and then comes back on. The dash for a brief second looks like you just turned the key on to start it and then all the lights go right back out. When the dash lights do turn on the car has a loss of power no doubt and then comes back on.


Thanks for the reply.
 

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I had a similar problem on my car. All dash lights went on, and it felt like the altenator is going out and I was pulling all volatage out of the battery. I got another altenator but when we tested it, it was ok. Turned out my battery was so fu**ed up, it was draining my system. New optima fixed the problem.

Try putting another battey in just to test it. The next thing I would recomment is driving to any autoparts store, they have voltage testers and will tell you for sure.
 

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I am having all the dash lights come on too. I haven't had a chance to check if its the alternator or battery. Battery tester shows that is still has a full charge.

It would be awesome if you could update this thread with what you have done to fix it, TT 6SPD 95 .
 

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Discussion Starter · #10 ·
BPUed said:
Tony it sounds like an altenator issue. I'll call you tonight!
I am taking off the alternator tonight and having one of my buddies from an alternator shop put a good load on it and see if it flakes out the same way. He said that it will only spin around 2,000 rpm though, so I hope it will be a good test.

Give me a call anytime...I appreciate it.
 

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Discussion Starter · #11 ·
Domino_2JZ said:
I am having all the dash lights come on too. I haven't had a chance to check if its the alternator or battery. Battery tester shows that is still has a full charge.

It would be awesome if you could update this thread with what you have done to fix it, TT 6SPD 95 .
I will definitely let everyone know. It may even end up being a ground issue, but that is doubtful.

Either way I will let you know what the problem is.
 

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I had these warning indication lights over the memorial day holiday... the ! light, the rear bulb, low oil pressure, and battery lights are indications of a failing alternator.

In my case, the alternator voltage regulator blew and was overcharging my battery...Anything over 1500rpms for me had a charging voltage of 15.5V to 17.5V. This is when all those indicator lights went off. I didn't get to it in time and the battery swelled up. With the 90 degree heat it boiled my battery and sprayed sulfuric acid onto my engine bay.... its a total mess and I'm still cleaning the crap up.
 

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Discussion Starter · #13 ·
I had an alternator/starter shop test the alternator tonight and they said it was perfect...they put a load on it and it did put out 150 amps like what it was designed to do. The voltage would never go up to the 16V I was getting before no matter what he did. His machine spins the alternator around 2,000rpm is what he said.

I went ahead and took it to an auto parts store and the tester went though a regulator test, diode test and I forget the last one. All tests were good.

I also had my battery tested and it was good, but the machine said it was low voltage. With no load I tested it at 12.4V at the time, but I am not sure if the machine was testing the voltage with a load and said it was low or it was no load and it was low?

My buddy at the alternator shop said that he could have a regulator for the alternator in a couple days if I wanted one and could have it in this week. Not sure if I want to fix a part that we don't know thats broken.

Well, thats the update on the situation so far.

I got everything back together and I have my battery terminals much tighter than what they were. Never had a problem with them before, but I am just trying everything at this point. Maybe at the very high rpm it had some kind of ground issue or something?

It started sprinkling here, so doesn't look like I will get to test it out tonight.
 

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Discussion Starter · #14 ·
rizinphoenix said:
I had these warning indication lights over the memorial day holiday... the ! light, the rear bulb, low oil pressure, and battery lights are indications of a failing alternator.

In my case, the alternator voltage regulator blew and was overcharging my battery...Anything over 1500rpms for me had a charging voltage of 15.5V to 17.5V. This is when all those indicator lights went off. I didn't get to it in time and the battery swelled up. With the 90 degree heat it boiled my battery and sprayed sulfuric acid onto my engine bay.... its a total mess and I'm still cleaning the crap up.
How did you know the regulator blew? Did you take it to an autoparts store to check out the alternator or something? Did they have to test it many times to know it was bad?

Maybe they can't tell mine is bad because they aren't spinning it high enough? Could that be possible I guess? RPM alone would cause the regulator to act funny?
 

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This isnt exactly like your problem Tony, but its kind of similar, my Trac and Trac off light are on at all time except when the car is in boost. The trac off button doesnt work unless the car is in boost, and then i can toggle Trac on or trac off.

This has stumped me for months and months, anyone have any ideas?
 

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Discussion Starter · #16 ·
I am going to try out the car again tonight with everything back together and the stinger terminals tightened up. I went ahead and ordered the regulator for it from the alternator shop and they said they would have it by Thursday. I guess I may have a left over regulator after all is said and done, but probably not.

I will let everyone know what happens.
 

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Discussion Starter · #17 ·
Ok, I have new information now to this thread as I tried it out again tonight. I made sure to stay in it at WOT just to keep things a little more simple and it the voltage DOES go up at WOT after all which will make the issue a little bit more simple to solve...not much, but a little. :)

I look at the Voltage and it starts out at 13.7V before the pull and then when I go to WOT it drops down to around 13.4V, as the boost is going up the voltage goes to 13.3V, 13.2V, 13.1V, 12.9V, 12.7V at peak boost and then it will go up to 16.5V when I am in boost for a little bit and it will not come back down until I let off the throttle and then it will go back down to around 13.7V.
The only time it seems to happen is at high rpm, but of course it apparently won't pull any power out of the alternator until high rpm looking at the voltage drop, so really that might not be saying anything talking about the RPM since that will be a "catch 22" if you will?

Although, I did have the alternator tested yesterday and they pulled 150 amps out of it at only around 2,000rpm and it never went up to 16V or anything like that...it only went down in voltage a little. I don't understand why this voltage is going up unless maybe it does coincidentally have to do with RPM, or maybe heat?

Any thoughts? Is that voltage drop too much as the RPM and boost rise?



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Discussion Starter · #19 ·
I was looking through all my other logs which were about 4 or so days before the high voltage started happening. None of the logs showed ANY sign of high voltages and the only change I made was I increased the boost to 24lbs.

To clarify my boost at 21-22lbs had no high voltage issues and the car would pull strong all the way up. After changing the boost to 24lbs the high voltage issues started happening.

Anyone have any ideas? I guess I will need to try and turn it back down to 21-22lbs and see if that eliminates the problem, but if it does eliminate the problem what could it be?
 

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Heat maybe??? Higher temps can cause quirky electircal issues! I missed your call, I'll try to reach you again tonight
 
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