Battery Problems With 93 Sc 400

[kalpi]

I have a 93 Lexus SC 400 (152000 miles) that has starting problems. The battery dies on me for no apparent reason and has to jump started or charged very frequently. I thought it was only in the cold months, but now it is year round. The battery, alternator, cables and starters have all been repeatedly tested and test ok. However, if you bring it home and try to start it the next day it will not start. Have left it with dealers(2) overnight, who "cannot replicate the problem". One dealer said since everything tests ok, he has no clue what to work on. Because the dealer could not find anything wrong with it, an independent mechanic suggested and changed spark plugs, wire set, ignition rotor, distributor cap and PCV valve. He also performed a complete tune-up. It still has the same problem. Last time I jumped the car, it fried my radio. This has been going on for almost 3 years. Once started, it runs good. I drove it 80 miles 4 days ago, parked it in the garage and it doesn't start again. Getting tired of jumpstarting it every time. I do not drive everyday, but not so infrequent that it would lose all its' power. Looks like the problem is getting worse. It used to be dead only if I didn't start it for 2 weeks, but now it is less than 4 days. This car has sentimental value and I would like to keep it as long as possible. Is there anything else I should look into? The dealers really aren't helping me. All they are interested is in talking me into buying a new car. Thanks for all your help in advance.

[raytbo]

Have you checked for any courtesy lights staying on, trunk, glovebox, vanity mirror or interior lights? When you jump the car, make sure you do it correctly or you could do a lot of damage to your electronics on this car!

[pj8708]

I am not a mechanic, but based upon what you have told us I have a couple of questions.

You say the dealer has checked the battery. Have they simply checked it to see if it will hold a charge, or have they checked to see how long it will hold a charge and if it is loosing it's charge overnight or over a few days. Secondly, have they checked the charging system to see if there is a leak to ground somewhere that is keeping the system from totally charging the battery over several days. I ask because you write that it may be a period of two weeks between times when the engine won't turn over and start.....maybe that is another point to clarify. Is the car not turning over or is something else happening when you say it won't start?

Paul