Weak Battery, Rough Idle?
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I havent driven my 944 in about 2 weeks and my friend comes into town so I let him borrow to 944. The next morning he calls me and says the battery is dead and that he could jump it, but after idling for a while it would start to run rough and die. So I went over to his house, jumped the car, and sure enough after a couple of minutes it starts idling really low and rough and wont rev above 1500 RPM's. So I went down to the local autoparts store and bought a new battery, installed it, and It was like I had a new car. Before, my idle had been rough and the car was kind of shaky when it first was warming up but after installing the new battery it ran beautifully. This morning my friend calls me up and sure enough the new battery is dead and it was doing the same thing. Even when the car had been jumped and I was driving it aoround it would still start to sputter, not rev above 1500, and die. I think the cause of the battery wearing out is the fans running for too long after the car has been shut off. How long should they usually run if the car was at full temp? thanks for the help.
-Andrew
P.S. I also have like 3 other wires coming off the positive side of my battery termninal. Is this normal? When i was going to loosen the positive side I touched the wrench to the firewall and it sparked pretty bad. Is the negaitve side of the terminal grounded to the firewall? Thanks.
-Andrew
P.S. I also have like 3 other wires coming off the positive side of my battery termninal. Is this normal? When i was going to loosen the positive side I touched the wrench to the firewall and it sparked pretty bad. Is the negaitve side of the terminal grounded to the firewall? Thanks.
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Hey, just so you know, i have hit the metal there with the wrench and made a spark doing the same thing. seems like a stupid design to me... anyway. mine still runs, well it didnt today but i havent started it all month and tried to when its 7 degrees out. i prob have crap frozen in my lines or somethin. hopefully. i dunno anyway, enough ranting. hpe you can figure it out. i think i have a few wires off my pos terminal too.
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I've hit the metal there with a wrench and even with the battery terminal while taking it out a couple of times but have had no real problem besides the sparks and the melted metal.
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It is not a stupid design, REMOVE THE NEGATIVE CABLE FIRST, ALWAYS, AND ATTATCH IT LAST and you will not arc weld you wrenches to the body of the car. As far as your running problem is concerned, it sounds like your alternator is not charging at all. Check to see if the alt warning light comes on with the key on but the engine off, if it does not then your alt. will not charge. The power to energize the alt. runs through the bulb in the dash, if the bulb is burned out the alt will not charge. If you have a voltmeter, check the voltage with the eng running, it should be 13.5 volts or above, if the batt. is weak and the alt is not working it will be around 12 volts.
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ok so I guess my fans are running for a normal amount of time so it must be either I am grounding out somewhere and or my alternator is shot. Am I thinking about this the right way. I appreciate the help.
-Andrew
-Andrew
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AWolf
Heads up: these cars have miserable ground issues:
easiest one to check: backside of the crossmember - clean, rough up, reconnect.
-Clean the actual contact for the main ground to the firewall and to the block - if you can reach it... with the battery disconnected!
-Actually, my least favorite, but most problematic have been the gauge pod grounds, but in the late models these are likely a bit different.
Under the driver's side dash is another ground bundle that's not too hard to get at.
Finally, there's a ground in the rear near the spare tire location that is a bundled ground (multiple grounds meet there and have coffee & tea together).
It's evil, but tracing down electrical gremlins will really help you become intimate with the car's counter-intuitive electrical goofs.
Good luck - let me know if you need more info on these points.
I hope you get more info from other posters too... SidVicsious I think is well versed in grounding hunts.
Heads up: these cars have miserable ground issues:
easiest one to check: backside of the crossmember - clean, rough up, reconnect.
-Clean the actual contact for the main ground to the firewall and to the block - if you can reach it... with the battery disconnected!
-Actually, my least favorite, but most problematic have been the gauge pod grounds, but in the late models these are likely a bit different.
Under the driver's side dash is another ground bundle that's not too hard to get at.
Finally, there's a ground in the rear near the spare tire location that is a bundled ground (multiple grounds meet there and have coffee & tea together).
It's evil, but tracing down electrical gremlins will really help you become intimate with the car's counter-intuitive electrical goofs.
Good luck - let me know if you need more info on these points.
I hope you get more info from other posters too... SidVicsious I think is well versed in grounding hunts.
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And by the way:
Your idling problem is weird, but I can confirm it; it happened in my car too.
I would consider buying an adjustable, or just a NEW voltage regulator from IceShark - it's worth every penny ($15-20 IIRC?), easy to install, and will recharge that battery much much more efficiently than the old system.
Your idling problem is weird, but I can confirm it; it happened in my car too.
I would consider buying an adjustable, or just a NEW voltage regulator from IceShark - it's worth every penny ($15-20 IIRC?), easy to install, and will recharge that battery much much more efficiently than the old system.