strange charging problem
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strange charging problem
Hello everyone,
I drive my 91 civic dx auto 60 miles each way to work into Boston daily. Recently, My alternator went, I replaced it with a brand new alternator. THe battery is also new. Distributer is new as well. Anyways the car runs fine when driving all the way untill I get to Boston and start sitting in traffic, when my battery light comes on. If I put the car in neutral and rev the engine hard, the light slowly turns off and stays off for a few seconds, then comes back on. This continues untill I am out of traffic and driving at speed again. I have tried to idle my car in the driveway for several hours before to see if it would do this but it only seems to do this after I have been driving for an hour or so and then sitting in traffic. I checked the belt and tension is OK, and alterator is charging at 14V. I'm baffled. Any ideas?
I drive my 91 civic dx auto 60 miles each way to work into Boston daily. Recently, My alternator went, I replaced it with a brand new alternator. THe battery is also new. Distributer is new as well. Anyways the car runs fine when driving all the way untill I get to Boston and start sitting in traffic, when my battery light comes on. If I put the car in neutral and rev the engine hard, the light slowly turns off and stays off for a few seconds, then comes back on. This continues untill I am out of traffic and driving at speed again. I have tried to idle my car in the driveway for several hours before to see if it would do this but it only seems to do this after I have been driving for an hour or so and then sitting in traffic. I checked the belt and tension is OK, and alterator is charging at 14V. I'm baffled. Any ideas?
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Thats it? Ive been through 3 alternators, I really dont think thats the problem at this point although I suppose it's possible. Any other ideas? I really dont want to go put in another alternator if its not gonna fix anything.
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Re: strange charging problem
Look, Slim, I can only guess at your problem from halfway across the freekin' planet.
I see about 4 different diagrams to choose from.
Hatch/Sedan or Wagon, and Mitsu or ND alts.
You have a pile of wires involved, and the PCM regulates the charging based on programming and the ELD input.
There are specific tests that you can do to diagnose this yourself if you have some know-how. Grab a shop manual and some test equipment and dig in.
Or play swaptronics.
I'll guess: Throw an ECM at it.
It's 20 years old, some old electronics fail from age.
(Mitsubishi built electronics were horrible for this starting around roughly 10 years old, capacitors leak electrolyte and ruin boards. Affected MANY manufacturers and MANY different electronic items! Far more than just cars!)
I'm reasonably sure that if you were to actually diagnose this while it has the problem happening, you could come to an accurate conclusion.
HTH
I see about 4 different diagrams to choose from.
Hatch/Sedan or Wagon, and Mitsu or ND alts.
You have a pile of wires involved, and the PCM regulates the charging based on programming and the ELD input.
There are specific tests that you can do to diagnose this yourself if you have some know-how. Grab a shop manual and some test equipment and dig in.
Or play swaptronics.
I'll guess: Throw an ECM at it.
It's 20 years old, some old electronics fail from age.
(Mitsubishi built electronics were horrible for this starting around roughly 10 years old, capacitors leak electrolyte and ruin boards. Affected MANY manufacturers and MANY different electronic items! Far more than just cars!)
I'm reasonably sure that if you were to actually diagnose this while it has the problem happening, you could come to an accurate conclusion.
HTH
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