Really weird problems I'm stumped

[sellin]

Ok so I’m new to this forum so thanks in advance for all the help. I am trying to fix my ex-wife’s 2001 Sportage…I know long story. Anyway she was driving to see me and called said it was starting to cut out and the lights where diming and the gauges where going crazy. So I told her to pull over I got in with a buddy and headed down to pick her up. I had assumed it was an alternator going out but no it was not. Anyway after talking to her a little more I got in and started driving home. Ok so here is what it is doing you get above 60 mph and the head lights start going dim then no head lights and gauges go funny and loose all power…get back down under 60 and it starts running fine again lights go back to normal. I am at a total blank and was hoping that maybe some of you guys might know what the problem is. Thanks again.

[PLP]

Originally Posted by sellin

…get back down under 60 and it starts running fine again lights go back to normal. I am at a total blank and was hoping that maybe some of you guys might know what the problem is. Thanks again.

OK, first determine if this is problem of speed or engine revolutions.
Drive it to 60 notice what rpm it is. Then slow down, and do kick downshift and see if high rpm is fine. Let it go to 60 or more.
I think it will be more related to speed. I do not know what sensors might be making problems.... BUT I would search for any loose cables. It sounds to me like maybe some (from alternator, battery, or ECM) wires are loose and when speed is high enough pressure of air pushes it/them to loose connection.
Its hard to say without more details, inspection and so on.

[dave2]

Can you unplug (disconnect)the alternator and the vehicle stay running? If so, do it and try again. Sounds like maybe something shorting out inside. If it doesn't stay running while disconnected, maybe you can have the alternator tested at a napa store or the like.

Dave

[tonup]

i think running it with the alternator disconnected you risk damaging the computer or electrics, I am not an auto electrician but I would check with your local sparky or dealer first.

[sellin]

PLP
Ok it’s not the engine RPM it is the speed of the vehicle. It’s got to be some ground someplace in the engine compartment. That is all I can figure out. I did talk to the Kia dealer today and he told me it’s most likely the alternator. The only problem I have with that is that if you take off the negative cable on a car while running it should keep going. I have tested the alternator and it’s in fine working order but like I said it only happens when going 60 and up. I guess it could be an intermittent problem in the alternator. I just don’t want to start throwing money at it guessing on parts that might fix the problem. Thanks again for all your guys help.

[PLP]

so disconnect the alternator and test drive.

Does it ALWAYS happen?

when you say that you loose power, all lights dim, then its more likely some kind of short circuit.
Again, to exclude the alternator itself - drive with disconnected alternator.

Inspect the positive wire coming to alternator and STARTER.

[tlstotelmyer]

I would check the chasis ground. I had something similar happen to my wifes Kia Sephia. The ground wire from the battery to the frame was rusted bad enough that it wasnt making good enough contact. It started with the window motors going slow then lights dimming, engine cranking slow then nothing at all. Hope this helps.

[sellin]

Thanks for all your guys help….Ok so I’m going to check all the grounds and wires from the alternator. Does anybody have a source for a wiring diagram for this Sportage or a link for one on the net?

[PLP]

Originally Posted by sellin

Thanks for all your guys help….Ok so I’m going to check all the grounds and wires from the alternator. Does anybody have a source for a wiring diagram for this Sportage or a link for one on the net?

yes,
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