The fix for my endless alternator failure's
Well it's not the gauge. After swapping the wires as mentioned above, I only had 12.6v feeding the gauge. At the battery 13.7. These readings were taken after a drive, with the car hot and in idle. Had 14.6v at the gauge AND the battery at start up, and during a 2-3 minute warm up period before the drive.
I'm running multiple circuits off of a 4th gen ignition relay. First thing I'm going to check is voltage in, and voltage out of that relay. Cold and hot. Will report back with updates.
I'm running multiple circuits off of a 4th gen ignition relay. First thing I'm going to check is voltage in, and voltage out of that relay. Cold and hot. Will report back with updates.
Well it's not the gauge. After swapping the wires as mentioned above, I only had 12.6v feeding the gauge. At the battery 13.7. These readings were taken after a drive, with the car hot and in idle. Had 14.6v at the gauge AND the battery at start up, and during a 2-3 minute warm up period before the drive.
I'm running multiple circuits off of a 4th gen ignition relay. First thing I'm going to check is voltage in, and voltage out of that relay. Cold and hot. Will report back with updates.
I'm running multiple circuits off of a 4th gen ignition relay. First thing I'm going to check is voltage in, and voltage out of that relay. Cold and hot. Will report back with updates.
Well it's not the gauge. After swapping the wires as mentioned above, I only had 12.6v feeding the gauge. At the battery 13.7. These readings were taken after a drive, with the car hot and in idle. Had 14.6v at the gauge AND the battery at start up, and during a 2-3 minute warm up period before the drive.
I'm running multiple circuits off of a 4th gen ignition relay. First thing I'm going to check is voltage in, and voltage out of that relay. Cold and hot. Will report back with updates.
I'm running multiple circuits off of a 4th gen ignition relay. First thing I'm going to check is voltage in, and voltage out of that relay. Cold and hot. Will report back with updates.
Just run the feed wire for the tester on its own relay directly to the battery.
Otherwise you can test draw on the system by pulling fuses to determine where the voltage drain is coming from
I've mentioned it a few times and others have noticed the dash gauge is not accurate anymore like when the car was new.
Otherwise you can test draw on the system by pulling fuses to determine where the voltage drain is coming from
I've mentioned it a few times and others have noticed the dash gauge is not accurate anymore like when the car was new.
Just run the feed wire for the tester on its own relay directly to the battery.
Otherwise you can test draw on the system by pulling fuses to determine where the voltage drain is coming from
I've mentioned it a few times and others have noticed the dash gauge is not accurate anymore like when the car was new.
Otherwise you can test draw on the system by pulling fuses to determine where the voltage drain is coming from
I've mentioned it a few times and others have noticed the dash gauge is not accurate anymore like when the car was new.
solved
All great ideas. Thanks guys. I finally found my problem.
I'm running a stock 4th gen f body underhood fuse/relay box. I pulled the box containing the ignition relay out of the mount and rolled it upside down. Started the engine to check voltages in,out and controlling the ignition relay. All seems fine. Decided to go for a ride and check it again. With the engine running I rolled the box right side up. As I did the ignition relay started chattering open and closed. The engine began sputtering and stalled. Ah Hah!
I was able to isolate the problem wire. 3rd gens have a heavy pink that supplies ignition 12v to basically everything in the engine bay that needs it. I used that wire as the hot side of the control circuit on the 4th gen ignition relay. When I removed the 4th gen fuse center from the donor car, I cut the wires about a foot down. The butt connector I used to connect the 3rd gen big pink to the hot side of the 4th gen ignition relay control.....had a bad crimp on one end.
I repaired the joint. SOLID 13.75 volts when hot under any driving circumstances, with anything on. My problem is now fixed. Thank god.
All great ideas. Thanks guys. I finally found my problem.
I'm running a stock 4th gen f body underhood fuse/relay box. I pulled the box containing the ignition relay out of the mount and rolled it upside down. Started the engine to check voltages in,out and controlling the ignition relay. All seems fine. Decided to go for a ride and check it again. With the engine running I rolled the box right side up. As I did the ignition relay started chattering open and closed. The engine began sputtering and stalled. Ah Hah!
I was able to isolate the problem wire. 3rd gens have a heavy pink that supplies ignition 12v to basically everything in the engine bay that needs it. I used that wire as the hot side of the control circuit on the 4th gen ignition relay. When I removed the 4th gen fuse center from the donor car, I cut the wires about a foot down. The butt connector I used to connect the 3rd gen big pink to the hot side of the 4th gen ignition relay control.....had a bad crimp on one end.
I repaired the joint. SOLID 13.75 volts when hot under any driving circumstances, with anything on. My problem is now fixed. Thank god.
Last edited by wph351; Aug 25, 2017 at 08:54 PM.
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Sweeeeeetttt!!
Wow... glad I'm not the only one with this problem.
I have a 3rd gen swapped, currently running a 145 amp alt that the local electric shop rebuilt for me. The plug is 4 prong but only one wire going to it.
At cold start, idling, I get 14+ volts. I gradually rev to 3500-4000 rpm and it drops to battery voltage ~12 and I lose fuel pressure/lights dim.
Is buying a kg3 alt off of LKQ really the only fix for this? I would think under minimal load (no lights on, etc) that the belt wouldn't slip at 3500 rpm. The belt is new and the tensioner is new as well.
I have a 3rd gen swapped, currently running a 145 amp alt that the local electric shop rebuilt for me. The plug is 4 prong but only one wire going to it.
At cold start, idling, I get 14+ volts. I gradually rev to 3500-4000 rpm and it drops to battery voltage ~12 and I lose fuel pressure/lights dim.
Is buying a kg3 alt off of LKQ really the only fix for this? I would think under minimal load (no lights on, etc) that the belt wouldn't slip at 3500 rpm. The belt is new and the tensioner is new as well.
This reman 145 looses voltage after 3500 rpm. Everything is grounded very well.
What did you do beside the alternator swap?
I just picked up a 140k mile kg3 alternator to swap on tonight to see if that helps
I did the "big 3" wire upgrade. I fried at least 2 reman alternators with high rpms. Just be very sure the associated infrastructure is good before pegging problems onto the alternator. I.E. Battery, battery terminals, trigger wire etc. etc.
Is that just additional positive and ground wires? I have the engine grounded on 3 spots, and 2 grounds off the battery.