02 mustang heeeelllpppp!!!!

Jsewell85

New Member
Aug 4, 2019
2
0
1
Alabama
Hello everyone I have a question. I have a 02 mustang, has high mileage on it. I have been having a problem with it lately. While driving my rpm and speedometer will go all the way up and then shoot all the way down. I can't drive over 40 without it doing this. If I turn my a/c on the car will die completely. Any ideas what this could be?
 
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The full gauge sweep is a DEAD giveaway that power is being lost. There's something wrong with the battery, battery cables, ground, or alternator.

Today's cars will not run right without a strong battery and alternator. When the PCM looses power it causes the PCM to relearn everything. Including the idle trim values.

Howto perform charging system voltage drop test
 
The full gauge sweep is a DEAD giveaway that power is being lost. There's something wrong with the battery, battery cables, ground, or alternator.

Today's cars will not run right witho
The full gauge sweep is a DEAD giveaway that power is being lost. There's something wrong with the battery, battery cables, ground, or alternator.

Today's cars will not run right without a strong battery and alternator. When the PCM looses power it causes the PCM to relearn everything. Including the idle trim values.

Howto perform charging system voltage drop test

ut a strong battery and alternator. When the PCM looses power it causes the PCM to relearn everything. Including the idle trim values.

Howto perform charging system voltage drop test

I've purchased and had installed a new battery as well as alternator to eliminate that but the problem still exists.
 
I've purchased and had installed a new battery as well as alternator to eliminate that but the problem still exists.
Well......doesn't this mean the problem has to be elsewhere?

Is the issue that you don't think that it's a power problem or don't know which part to replace or where to look?

Note, don't overlook the role that a weak or loose ground could play in this. Bad power feed or loose ground. As far as the cluster itself is concerned it's all the same.

Do you have a volt-ohm meter (VOM) and a test light and are you willing to use it?