Just installed Mechman Alternator, Battery Light comes on now
#46
Now I have another stock alternator, and I have narrowed the situations down. Being in park my car holds a steady charge at 13.9-14.1 with head/tail lights on, A/C on, and interior lights and the RPM's are at 680-790. When I go into reverse or drive, while stationary (holding brake), with all those accessories on my voltage dies down 12.9 and keeps going down and then holds steady at 12.4-12.5, my RPM's are down to 480-520 and it sounds like my car isn't on anymore. The minute I begin to move the RPM's go up and so does my voltage. Is there a way to raise RPM's for our cars while in drive or reverse? I need the RPM's above 550 so the alternator will stay on and then I think I will be golden. I have yet to find a corroded or not connected ground. These situations happen with any alternator I throw on the car, been a real gremlin.
#47
Rookie
Thread Starter
Join Date: Jul 2013
Location: Georgia
Posts: 66
Likes: 0
Received 0 Likes
on
0 Posts
Not with the new alternator I got, I still have the Mechman alternator. I am going to put it on my girlfriend's IS300, I believe they have the same set up, so they alternator should fit in hers. Once I finally install it on hers, I will do the rev test (that's what I call it). I will know if it is the alternator or the car at that point.
#48
My battery light still comes on if i go past 5k rpm, so when im on the freeway gunning it, the light will stay on once the needle goes past 5k until it shifts. I don't notice any difference in the power, my sub still pounds. nothing irregular
#49
Rookie
Thread Starter
Join Date: Jul 2013
Location: Georgia
Posts: 66
Likes: 0
Received 0 Likes
on
0 Posts
Yeah I don't the battery light is a real problem, maybe a precautionary or maybe the computer actually thinks it is getting more Volts (i.e 14.5+ volts) since the amperage is much higher. Just a thought. I still get massive voltage drops, I beginning to believe in bad ground (THAT I CAN'T FIND), a bad wiring harness (I have no bottom engine cover, maybe something get on cut, scraped, or soaked in rain water), or the battery. I haven't been able to change batteries since I have been extremely busy. Maybe I can go buy a new battery this weekend, new battery terminals and see what happens.
#50
Driver School Candidate
iTrader: (1)
I stumbled upon this thread while searching for people's experiences with high output alternators. My stock alternator is holding up fairly well under the insane load my 1800 rms watt system is putting on it, however I know I'm not getting all of the power out of my amps as I should since I done have the proper current/amps to feed them. Seems as if the mechman alternators are not being properly bench tested and going through QA prior to being received by customers. I'm not a mechanic and can't imagine spending $450 on a alternator plus $250 for install just to have to repay $250 for labor to have it uninstalled to send back then another $250 for reinstall for the piece still not work properly. Charlie is the shipping fee the biggest reason you don't want to send it back to mechman? What alternator did you replace it with that is not currently giving you any issues?
#51
Rookie
Thread Starter
Join Date: Jul 2013
Location: Georgia
Posts: 66
Likes: 0
Received 0 Likes
on
0 Posts
I stumbled upon this thread while searching for people's experiences with high output alternators. My stock alternator is holding up fairly well under the insane load my 1800 rms watt system is putting on it, however I know I'm not getting all of the power out of my amps as I should since I done have the proper current/amps to feed them. Seems as if the mechman alternators are not being properly bench tested and going through QA prior to being received by customers. I'm not a mechanic and can't imagine spending $450 on a alternator plus $250 for install just to have to repay $250 for labor to have it uninstalled to send back then another $250 for reinstall for the piece still not work properly. Charlie is the shipping fee the biggest reason you don't want to send it back to mechman? What alternator did you replace it with that is not currently giving you any issues?
#53
Driver School Candidate
Everyone: Please don't overlook the mechanical aspect of this problem. If you can create the problem in your driveway, check to see how the engine is reacting when the light illuminates. Be sure your cables are not being pulled during this transient.
#54
Rookie
Thread Starter
Join Date: Jul 2013
Location: Georgia
Posts: 66
Likes: 0
Received 0 Likes
on
0 Posts
I have not installed it into my girlfriend's car as of yet, she is hesitant to install it since she believes it will mess up her car as well. I keep telling her it's my car that's boned, so hers would be fine. For value, I stated that in my last post, but it only cost me 180 bucks (went 3 times to my mechanic to uninstall/reinstall.) Then I started doing it myself, so it doesn't cost me anything now, 30 minutes is what it cost. She goes out of town this weekend with her car, so I don't want to mess up somehow anyway, so I will be putting it in next weekend (the 21st) and will update. I just have not had the time either to do anything with work. JimBob, what exactly are you talking about? Cables as in power/ground cables? They aren't being pulled at all. I have noticed if I let my car sit for a day or 2, that it is hard to crank at first, then turn key off position, turn the key back on position and it cranks. I do to need have my starter and IAC motor checked, and possibly a new battery, but not in the right position to buy that items right now. Probably a few weeks away from buying all that or at least 2 weeks away to get the IAC motor. I WILL update if/when I get my car working right. Who knows, could be a leaking capacitor which I will never find, but will have to bring to Lexus and have them diagnose the problem; trying to avoid the dealership at all costs so I don't have to throw so much money.
Last edited by CharlieD93; 06-09-14 at 06:30 AM.
#56
Rookie
Thread Starter
Join Date: Jul 2013
Location: Georgia
Posts: 66
Likes: 0
Received 0 Likes
on
0 Posts
Actually, I never got to install it into her car because we decided to split up. So I do not know if it is an alternator issue or my car is the issue. I am selling the alternator at this point as I am getting a new car as well, I did fix the rpm and voltage issues by getting a new IACV. If someone wants to figure it out or might have a different experience with their GS, then they can pm me to buy the alternator. It is Mechman 240 Amp that still looks new, maybe 6 hours in my car at the most. So sorry for not answering this problem alternator wise.
#57
Lexus Test Driver
iTrader: (1)
I installed a 320A Mechman on my 1999 LS400 over the weekend, and I also have a battery light on my dash. Unlike the OP, mine stays on constantly instead of briefly coming on under load. My install consists of the alternator itself, a 1/0 power cable (alternator positive to battery positive) fused for 350A, and I have also grounded the alternator case to the chassis with 1/0 cable as well.
Thread
Thread Starter
Forum
Replies
Last Post
99custom
ES - 1st to 4th Gen (1990-2006)
12
09-16-18 06:42 AM
SCFactory
SC- 1st Gen (1992-2000)
2
12-15-15 05:45 AM