LS1 trans am battery cable to alternator replacement?

**transamgirl** · 06-08-2007, 09:53 PM

I just put on a 150 amp alternator and I'm still haveing my engine surging at idle in park and the volt meter in car reading 12. I am going to replace the cable but not sure what cable I need. I noticed that mine has the black wire running to the alternator, one red one running somewhere under to the starter I guess, and another red one runngin to the fuse boxes all clamped into one with the sleeve. I looked online and can only find one with two wires. one to alternator and a thin one hooked up to it that runs into a plug or clamp. any suggestions?

**TACE02** · 06-09-2007, 04:27 AM

explain this surging in park??? Battery or motor? And how does it affect it when you give it a little gas? When your battery reads 12 what is the RPMs at?

**transamgirl** · 06-09-2007, 05:51 AM

it feels like the engine shakes a little. you can fell the car shake inside when it does this. sometimes it shakes a little more than other times.not in gear though.when i give it a little gas the volt meter stays the same but the lights will slightly dim for about a sec. it was a lot worse before i put the high amp alternator on. the voltage dropped and the car seemed like it was about to die.my husband has a corvette and the lights do the same for about a sec when he hits his gas. no change in voltage though. rpms are at 600

**transamgirl** · 06-09-2007, 05:57 AM

it's been doing this for about a year. we were told a few months ago the alternaotr volt. regulator was going bad. about 2 years ago i put in new plugs and wires, trans fluid changed, radiator fluid, oil always changed early, new pcv. i checked a spark plug last night and it looked good but it was loose. it's got 118,000 miles on it and i've only drove it hard maybe four times over the past five years just to kick it out and spped up fast otherwise i'm always carfeul how i drive it. i want it to last a long time

**TACE02** · 06-09-2007, 08:20 AM

600??? that is a low idle. should be around 800 anything less than that would cause low volts from the alternator due to not turning it fast enough. do you have any after market mods? What does your batt. voltage look like at 1500 RPMs steady. Sounds like you might have a different problem. PCM isn't getting a good signal from somewhere perhaps. How does your car feel during normal driving?

**TACE02** · 06-09-2007, 08:25 AM

O, and you don't have to be soooo careful. LS1s like a little gas every now and then, keeps them good and lubricated. What octane do you use? Do you do full tune ups to include changing fuel filter? Asking all simple questions, but who knows it might be something really simple that has been overlooked. you might even be able to get a good answer by letting a GM dealership look at it. Kinda pricey, but a good running fixed car is worth it.

**transamgirl** · 06-09-2007, 09:46 AM

only mods are reroute of small hose from radiator to throttle body, egr tube cut shorter and air box upgrade to raptor hood from flat hood. had dyno two years ago and said it was running slightly rich but not too bad. i just put a 4 gauge wire on and it now idles at 800. i started it quickly and for the minute i was sitting there i didn't feel shaking so maybe that's my problem. i know the person who had the car before me put a flowmaster exhaust on it so it's louder. dyno at 342 at engine. hopefully it's fixed. i'll take it out later to see

**TACE02** · 06-09-2007, 10:25 AM

good luck, hopefully that did it.

**transamgirl** · 06-09-2007, 04:36 PM

it did help some. when driving the car feels fine and even sitting still in gear is fine but when i'm in park and sitting the car kinda seems like it's missing. when i get by the exhaust i hear a hesitation or pause in the sound about every few second. almost feels like your going over some small bumps in the road but your sitting still

**94whtta** · 06-09-2007, 05:15 PM

i know nothing about the ls1's but could it be a spark plug wire arching against the manifold. Everything you describe sounds like what my lt1 has been doing for the past couple days because of a bad plug wire. Also you may want to do the other 2 of the big 3, can help your charging system.

http://www.the12volt.com/installbay/...TID=73496&PN=1

good luck hope you get it fixed

**transamgirl** · 06-09-2007, 05:26 PM

thanks i'll check and check the plugs to see if they are loose.

**rbob93** · 06-09-2007, 06:25 PM

LS1 engines run a little rough

**transamgirl** · 06-09-2007, 07:46 PM

I took the car out tonight and it ran at 14-15 volts while driving and drove great not problems or lights pulsing at all. get in the driveway and come to a stop still in drive and the volt drop to 12 or toching the yellow area. put it in park and it goes back to 14. ??? one thing i don't know a lot about is the electrical stuf on the car. i'm o.k. with all the other mechanical stuff

**desliger** · 06-13-2007, 07:15 PM

transamgirl, if you find a part number, or where to find the cable, please post it. I know some one who needs the same cable!

Thanks!!

**transamgirl** · 06-13-2007, 08:56 PM

I just went to o'reilly auto store with my old cable and asked for 4 gauge to replace it. they measured and cut it for me. only problem was that cable has a starter cable and a fuse box cable attached so we had to cut both as close to the batter hook up as possible to reuse it. we then had to buy a new clamp to clamp all three cables together to hook back up to the battery. I think the cable was about 4 feet long. hope this helps.

**desliger** · 06-14-2007, 05:36 AM

Thanks! I guess my friend actually needs just the battery cable ends (some one modified it to some type of clamp on instead of post). He might have to buy the whole cable..

I'm glad you got yours working though!!

**transamgirl** · 06-14-2007, 05:53 PM

yeah, my only problem now is that i took it to town today and the voltage gauge in car is staying at 13 and when I stop and have the a/c or lights on it drops into the yellow zone. i'm going to have it tested Fri.