electro surprises
redpepe
08-27-2007, 07:02 PM
hi metro brothers and sisters,
i just lost electrics and electronics on my '91. i'm charging the battery and i suspect it is the alternator and will begin testing tomorow. btw .... i have only 320k miles and who woulda thunk and alternator would break down soooo soon!
for the curious, i first lost the radio ... then the turn signals. then it wouldn't start and after jumping it i almost made it home but .....
no check engine light til i couldn't start.
i must have been driving on the battery for a few days and it finally went below the critical voltage for the computer / engine.
my last post concerned a thump in the wheels. i replaced the rt drive axle and will do the left next but i still suspect outta round tires and will replace these when more worn. low priority at the moment.
best, redpepe
i just lost electrics and electronics on my '91. i'm charging the battery and i suspect it is the alternator and will begin testing tomorow. btw .... i have only 320k miles and who woulda thunk and alternator would break down soooo soon!
for the curious, i first lost the radio ... then the turn signals. then it wouldn't start and after jumping it i almost made it home but .....
no check engine light til i couldn't start.
i must have been driving on the battery for a few days and it finally went below the critical voltage for the computer / engine.
my last post concerned a thump in the wheels. i replaced the rt drive axle and will do the left next but i still suspect outta round tires and will replace these when more worn. low priority at the moment.
best, redpepe
91Caprice9c1
08-28-2007, 02:55 AM
hi metro brothers and sisters,
i just lost electrics and electronics on my '91. i'm charging the battery and i suspect it is the alternator and will begin testing tomorow. btw .... i have only 320k miles and who woulda thunk and alternator would break down soooo soon!
for the curious, i first lost the radio ... then the turn signals. then it wouldn't start and after jumping it i almost made it home but .....
no check engine light til i couldn't start.
i must have been driving on the battery for a few days and it finally went below the critical voltage for the computer / engine.
my last post concerned a thump in the wheels. i replaced the rt drive axle and will do the left next but i still suspect outta round tires and will replace these when more worn. low priority at the moment.
best, redpepe
Clean all the ground connections between the battery and the body and the battery and the engine. Also be sure that your battery terminals and post connections are clean and tight. After charging, have the battery load tested.
FWIW axles will not cause a thump in the wheel/tire assemblies. Suspect either wheel or tire runout, or a combination. What I like to do to test for this when a car shimmys at speed is very similar to what I do to test for bad wheel bearings. Lift and support safely (ON JACKSTANDS) the front of the car, and let it idle in 5th gear. Take a straight board and slowly lever it up toward the spinning tire just enough to touch it. If it skips instead of contacts steadily with the board you've got runout. If the tires have excessive runout it could be because of bad alignment/struts. Or it could just be worn out old tires (tread seperation as you aptly mentioned). Goodluck and post back with the strange electrical symptoms.
-MechanicMatt
i just lost electrics and electronics on my '91. i'm charging the battery and i suspect it is the alternator and will begin testing tomorow. btw .... i have only 320k miles and who woulda thunk and alternator would break down soooo soon!
for the curious, i first lost the radio ... then the turn signals. then it wouldn't start and after jumping it i almost made it home but .....
no check engine light til i couldn't start.
i must have been driving on the battery for a few days and it finally went below the critical voltage for the computer / engine.
my last post concerned a thump in the wheels. i replaced the rt drive axle and will do the left next but i still suspect outta round tires and will replace these when more worn. low priority at the moment.
best, redpepe
Clean all the ground connections between the battery and the body and the battery and the engine. Also be sure that your battery terminals and post connections are clean and tight. After charging, have the battery load tested.
FWIW axles will not cause a thump in the wheel/tire assemblies. Suspect either wheel or tire runout, or a combination. What I like to do to test for this when a car shimmys at speed is very similar to what I do to test for bad wheel bearings. Lift and support safely (ON JACKSTANDS) the front of the car, and let it idle in 5th gear. Take a straight board and slowly lever it up toward the spinning tire just enough to touch it. If it skips instead of contacts steadily with the board you've got runout. If the tires have excessive runout it could be because of bad alignment/struts. Or it could just be worn out old tires (tread seperation as you aptly mentioned). Goodluck and post back with the strange electrical symptoms.
-MechanicMatt
redpepe
08-28-2007, 11:06 AM
thanks matt. i'll check the grounds and then isolate components. i keep the engine compartment very clean. i think the batt is good but you're right, it could be the problem. using jumper cables, a friend charged the batt in a few minutes of connection and doing this twice allowed me to drive the 5 miles to my shop.
i agree that the axles are not likely to be the thumpers. it's actually a more complex sound and harmonic. the rt had a torn boot and both have met my mileage expectations. this will be the fourth set. i did the rt only temporarily to isolate and check the left. the struts are the originals but they seem ok.
i checked the runout a while ago and it was about an eighth of an inch on all which is about twice the max spec as i understand it. the tires have about 28k and i'll probably keep rotating and balancing for the duration though i'm tempted to shave 'em. i thought the dealer would replace them but they backed out.
i agree that the axles are not likely to be the thumpers. it's actually a more complex sound and harmonic. the rt had a torn boot and both have met my mileage expectations. this will be the fourth set. i did the rt only temporarily to isolate and check the left. the struts are the originals but they seem ok.
i checked the runout a while ago and it was about an eighth of an inch on all which is about twice the max spec as i understand it. the tires have about 28k and i'll probably keep rotating and balancing for the duration though i'm tempted to shave 'em. i thought the dealer would replace them but they backed out.
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