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Discussion Starter · #1 · (Edited)
Hi everybody!

It's been awhile, but I've got a problem now that I can't seem to get to the bottom of.

The car drives fine, barely any problems, idle runs a tiny bit low, which may have to do with the errors it's throwing.

When I start the car in the morning, I haven't got any errors EVER. The car drives fine, no problems shifting or anything. After driving for about half an hour, I get the 3 yellow traction control/ABS/DTC lights that go on. When I read the code, it tells me P0751 Shift Solenoid "A" Performance or Stuck Off. Sometimes it also throws a P0500.

It's worth to mention that if I start it again after about 15 minutes, having done whatever I needed to do, sometimes the codes are already gone by themselves. but leave the car for an hour or more, and the codes are always gone.

Since the car is driving fine, I haven't really given it much attention. It has gone into trans failsafe mode twice in one year, but once I turn the car off and on again it's fine.

When I reach speeds of about 100km/h, the battery light goes on. When I let go of the throttle a bit, it turns off again and stays that way. I've put a new battery in, thinking that that was the problem, but same. I checked all the connectors and stuff, and they all seem to be fine.

Are these several problems? Is it one? I don't really have the budget to start switching out things to see if they solve the problem, without knowing what the problem is.

Help would be much appreciated!
 

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Wingnut
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check the alternator output....the battery light is kind of a misnomer in these cars, it indicates that the battery isnt charging, not that the battery is bad. its not unusual for the lights youre getting to come on when theres a fault directly related to a charging system malfunction.
 

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Discussion Starter · #3 ·
check the alternator output....the battery light is kind of a misnomer in these cars, it indicates that the battery isnt charging, not that the battery is bad. its not unusual for the lights youre getting to come on when theres a fault directly related to a charging system malfunction.
Hmm, might be, not sure how to check this, but it's true that the power steering reservoir has been leaking a bit, it's right over the alternator. Maybe that's mucked up the alternator?
 

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What is the voltage at the battery with engine running?
 

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Discussion Starter · #5 ·
What is the voltage at the battery with engine running?
Engine on at idle it’s 13.3-13.8
When driving it fluctuates between 13.7 and 14.2
At around 60km/h-110km/h when accelerating it dips to 12.0-12.7 until I let go of the throttle, and then it returns to earlier numbers. That’s when the battery light comes on.

maybe something wrong with the connectors? I already cleaned and sanded the battery connectors, maybe some electrical cleaner at the alternator?
 

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Clean the inside of the alt connector and make sure the slip rings don’t have any leaking PS fluid on them.
 

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Discussion Starter · #7 ·
Clean the inside of the alt connector and make sure the slip rings don’t have any leaking PS fluid on them.
bought some electrical cleaner, sprayed the alternator and connector. I checked the battery connectors again, and my negative wasn't smooth at all. I assumed it was smooth when I was sanding it, and I just tried to get a small layer off. Anyhow, I smoothed it all out, sprayed it and put it back. On the way home, the battery light didn't turn on once. Before it would dip below 12V, to about 11.2V, but this time it didn't go below 12.4V, and only for a split second.

My traction control/ABS/DTC lights were still on. They should be gone by morning, and if the battery thing is fixed, we'll see if those lights come back or not. Thanks for the help so far, and I'll update tomorrow
 

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Discussion Starter · #8 ·
Well, problem isn’t gone, but it does seem a bit better. Should I take the alternator out, take it apart and clean it? I take it that that would be the only way of getting to the slip rings. Is this possible? Is it even plausible? Or should I just put in a new alternator?
 

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If this is an i6 take it out would be the best way to clean it, especially the rear air cooling cover/duct. It could be packed with leaves, etc.
 

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Discussion Starter · #10 ·
If this is an i6 take it out would be the best way to clean it, especially the rear air cooling cover/duct. It could be packed with leaves, etc.
I've tried to find out how to clean it, but how would I go about that? I get cleaning out the leaves and stuff, but how would I go about cleaning the alternator itself?
 

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I should have asked you if this is an original alternator and how many miles are on the car.
Have the brushes every been replaced? Along with the back of the alt packed with leaves the brushes that make contact with the slip rings could be worn out.
Here’s a lot of alternator info.
Alternator rebuild
 

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Discussion Starter · #12 ·
Okay, so eventually I decided to change the alternator, I put in a new one yesterday, and the battery light seems to be fixed. I did go on an hour long drive where the traction control/abs/dtc lights didn’t come on. However, on my return trip they came back. 😞

I can the diagnostics, and now only p0741 shows up.
It seems that the power steering lines connected to the reservoir were the culprit of damaging my old alternator, the clamps on them weren’t tightened enough, and caused them to leak, so that’s fixed now as well.

I had hoped that the traction control/abs/dtc would be fixed too, or maybe this is something the transmission computer needs to adapt to again?
 

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Wingnut
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what are the ABS codes? it seems that youre only looking at the DME codes with a OBDII reader.
 

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Discussion Starter · #15 ·
Thanks for all your input so far, I’m first going to do a transmission computer reset to factory, it’s a simple procedure, and because of the earlier issues with the alternator, it might’ve learned some bad things. Maybe that solves it. Otherwise, my next step will be to replace the transmission fluid, I’ll not be doing this for awhile though, sometime during the summer I’ll look into this. Hopefully the reset solves it. I’ll keep everyone updated.
 

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Okay, so eventually I decided to change the alternator, I put in a new one yesterday, and the battery light seems to be fixed. I did go on an hour long drive where the traction control/abs/dtc lights didn’t come on. However, on my return trip they came back. 😞

I can the diagnostics, and now only p0741 shows up.
It seems that the power steering lines connected to the reservoir were the culprit of damaging my old alternator, the clamps on them weren’t tightened enough, and caused them to leak, so that’s fixed now as well.

I had hoped that the traction control/abs/dtc would be fixed too, or maybe this is something the transmission computer needs to adapt to again?
Just re-tightening that clamp on the bottom of the PS fluid reservoir typically won't do it. The geometry of the hose just doesn't allow a tight seal. The more you crank down on the clamp the more you damage the hose. You will likely need to replace that hose. Some people have had success with trimming a short section of that hose and reattaching, but you're only delaying the inevitable. Replace that hose to effect a longer repair.
 

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Discussion Starter · #17 ·
Just re-tightening that clamp on the bottom of the PS fluid reservoir typically won't do it. The geometry of the hose just doesn't allow a tight seal. The more you crank down on the clamp the more you damage the hose. You will likely need to replace that hose. Some people have had success with trimming a short section of that hose and reattaching, but you're only delaying the inevitable. Replace that hose to effect a longer repair.
I don't know, the hoses seemed to be fine, but they were literally moving about freely at their connection point with the reservoir. When I tightened them, they at least kept in place, and weren't able to move around. I'll keep an eye on it, but when I checked yesterday, there was no fluid leaking anymore. Thanks for the tip though, I don't want to keep replacing alternators.
 

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Wingnut
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+1 on cutting the hose back an inch if possible..the hose hardens where its clamped, doesnt like taking a new shape
 

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Discussion Starter · #19 ·
I've been driving the car for quite some kilometers now, and it's not leaking any power steering fluid anymore, so it really just seems that the clamps weren't tight enough. As I said, the other lights do come on as described above. I'll give another update once I've replaced the transmission fluid and filter.
 
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