This is for a friend of mine. We are trying to figure out a weird electrical prob on his car.
1994 GT vert 5-spd.
We've put 3 alts on this car and 2 batteries trying to figure it out. latest alt is a brand new Ford OEM.
Basically, the voltage fluctuates as if the regulator isn't working. With the first batch of alts, the voltage would stay consistant 12.5 v as if the alt just wasn't working. As you drove, it would go down. Rev the engine and it does not jump at all. It's almost like it was running off the battery.
Fast forward to latest alt. Voltage will hang at 12.4v and then occasionally jump to 14V and hold for a min or two, then would drop back down to 12v. The gauge on the dash reflects this as well going to the center when the voltage rises to 14 and then dropping to N when the voltage drops. This is on its own with no RPM changes.
We've replaced both battery terminals, new batteries, new alternators, replaced a questionalable stator plug wire and cleaned up some connections. No change.
We are going to start ohming out the wiring next, but wondering if anyone had any input of expeirence. It's like the votage regulator only works when it wants to. I checked the power to the large 3-wire plug on the alt and one of the wires does have constant 12V+ from the battery (with the car off), so perhaps something is being lost on the other wire?
1994 GT vert 5-spd.
We've put 3 alts on this car and 2 batteries trying to figure it out. latest alt is a brand new Ford OEM.
Basically, the voltage fluctuates as if the regulator isn't working. With the first batch of alts, the voltage would stay consistant 12.5 v as if the alt just wasn't working. As you drove, it would go down. Rev the engine and it does not jump at all. It's almost like it was running off the battery.
Fast forward to latest alt. Voltage will hang at 12.4v and then occasionally jump to 14V and hold for a min or two, then would drop back down to 12v. The gauge on the dash reflects this as well going to the center when the voltage rises to 14 and then dropping to N when the voltage drops. This is on its own with no RPM changes.
We've replaced both battery terminals, new batteries, new alternators, replaced a questionalable stator plug wire and cleaned up some connections. No change.
We are going to start ohming out the wiring next, but wondering if anyone had any input of expeirence. It's like the votage regulator only works when it wants to. I checked the power to the large 3-wire plug on the alt and one of the wires does have constant 12V+ from the battery (with the car off), so perhaps something is being lost on the other wire?