1992 Sable startup problems

[John.breen]

My stepdaughter has the above-stated car and has become stranded a couple of times in the past month - unable to start her car without a jump. She is in college and only drives her car on the weekends. When she does drive, it is anywhere from a 10-minute drive to a 3-hour drive. When the car fails to start, it is often after she has been driving for some distance, then stops her vehicle, then soon after tries to start it again. Last night we gave her a jump and followed her home. No problems. When I went to start it today, it wouldn't turn over. Seemed like a dead battery.

I put a multimeter on the battery which read 12.3. When the key was turned, it immediately dropped down to about 3.4 without starting (battery sounding like it dies). It did this a couple of times, after which I stopped trying. But after each attempt, the battery seemed to read 12.3 again.

Running the same test on my Accord, it started at 12.7, dropped to 10.8 while starting up, then levelled off about 14.7 thereafter, which I've been told is normal.

This is probably pretty basic, but I really don't know enough about voltage regulators and alternators to know what to try.

Suggestions?
Thanks a ton in advance.

John

 

[breezer]

a new battery?

also what voltage is going to the battery when engine is running (dissconect one lead, other wise you will be reading battery too) if its 12V or above its battery that is at fault

 

[david and julie]

Agree with Breezer it is probably the battery,that is assuming you have nothing else going to earth.

DO NOT run your engine with any battery leads disconnected it may ruin your alternator.

Give all the leads and earths a good clean including the one from chassis to engine/gearbox. If that doesn't help it will be better to take car to auto electric shop and have them test both battery and alternator.

In the UK they would probably not charge you for this test,if you bought the parts from them. Is it not the same where you live?

 

[david and julie]

John...... I forgot to mention, for safety and to avoid any possible damage caused by sparks,always remove the battery earth first and replace it last on assembly. It is usually inevitable your spanners bang something whilst working.