'92 SC300 Electronics Woes. At my wits end
#1
Driver School Candidate
Thread Starter
'92 SC300 Electronics Woes. At my wits end
So I have been chasing a problem the last few months and I have no idea what it could be anymore. It only really happens when the car is in drive and I'm not touching the throttle. Sometimes it will happen in park and reverse so long as I'm not touching the throttle as mentioned before. When it has this problem the voltage coming from the alternator will fluctuate rapidly and randomly anywhere from 12.5v to almost 16v. So instantly I thought that my alternator was going bad. Just put a new one in yesterday and it started doing it again tonight. Now the only thing I can think of is a bad sensor or an ECU problem.
I have went through all the connections from the alternator to the battery ground and they all look fine. I will try to isolate the problem tomorrow but I have no idea where it could be originating from. Any help would be great! Thanks!
I have went through all the connections from the alternator to the battery ground and they all look fine. I will try to isolate the problem tomorrow but I have no idea where it could be originating from. Any help would be great! Thanks!
#3
Driver School Candidate
Thread Starter
I have checked them and the main ground to the frame and the block has been re done in the past 5-8 years. Do you know how exactly the voltage is regulated? is it all done by the alternator or is it controlled from somewhere else?
#5
Driver School Candidate
Thread Starter
Well I'd rather keep from selling the car but if I can't figure this out I can't just keep dumping money into it. I've already chased many other problems around for years.
#6
Your idle has to be above 500 rpm, esp. if the A.C. is on. I would inspect the plug in to the alt. for loose wire or burned connectors on the plug, also that the main battery cable end that bolts on the alt. is not loose.
#7
Driver School Candidate
Thread Starter
Also, when I am stopped at a red light the idle seems to be stressed but the RPM doesn't really change but it sounds like the engine is pulling hard on something and when I have my turn signal on every time the relay fires the engine bogs down a bit as well. Could these problems all be linked to the same thing?
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#9
Driver School Candidate
Thread Starter
I haven't had it serviced but it has been replaced in the past threeish years with a confirmed working one. Should that be my next step? Where or how did you get yours serviced?
#10
Lead Lap
iTrader: (8)
I had mine serviced locally by a circuit board specialist. Tanin and Drift Motion are popular options, and I believe Daryl Geller is somewhat near you.
If the "confirmed working one" hasn't been serviced, it's just as likely to be going bad now. The original capacitors have a ~14 year shelf life.
https://www.clublexus.com/forums/ls4...capacitor.html
If the "confirmed working one" hasn't been serviced, it's just as likely to be going bad now. The original capacitors have a ~14 year shelf life.
https://www.clublexus.com/forums/ls4...capacitor.html
#11
So I have been chasing a problem the last few months and I have no idea what it could be anymore. It only really happens when the car is in drive and I'm not touching the throttle. Sometimes it will happen in park and reverse so long as I'm not touching the throttle as mentioned before. When it has this problem the voltage coming from the alternator will fluctuate rapidly and randomly anywhere from 12.5v to almost 16v. So instantly I thought that my alternator was going bad. Just put a new one in yesterday and it started doing it again tonight. Now the only thing I can think of is a bad sensor or an ECU problem.
I have went through all the connections from the alternator to the battery ground and they all look fine. I will try to isolate the problem tomorrow but I have no idea where it could be originating from. Any help would be great! Thanks!
I have went through all the connections from the alternator to the battery ground and they all look fine. I will try to isolate the problem tomorrow but I have no idea where it could be originating from. Any help would be great! Thanks!
Give us a call and we can talk more about the ECU when it is convenient for you. We are happy to help out!
__________________
TANIN AUTO ELECTRONIX
262-456-4147
contact@taninauto.com
www.taninautoelectronix.com
TANIN AUTO ELECTRONIX
262-456-4147
contact@taninauto.com
www.taninautoelectronix.com
#12
Driver School Candidate
Thread Starter
So Tanin would I be able to call tomorrow? I would like to ask some questions on what to do. I was on vacation the past week and didn't want to respond to be honest. This car is my daily so I can't have it down for more than a day or two. Tomorrow I'll re-do the ground wiring and check all the connections on the alternator again.
#13
In Recovery Mode
iTrader: (11)
Where did you get your alternator? In rare cases, the replacement alternators can be faulty. In some cases, the alternator is just a rebuilt until that was previously used. This is why I encourage the purchase of OEM alternators.
Speaking from experience here. Took 4 month for my auto zone alternator to start having issues.
Speaking from experience here. Took 4 month for my auto zone alternator to start having issues.
#14
Driver School Candidate
Thread Starter
It's funny you say that. I just swapped an alternator in about a year ago and fearing that it was the classic "part waits until end of warranty to fail" ordeal that always seems to happen to rebuilt parts. So I went and bought an OEM alternator and swapped it in two weeks ago and the problem stayed. I actually just sent the ECU out to Tanin and we'll see if they find/fix the problem. I'll keep the thread updated.
#15
So Tanin would I be able to call tomorrow? I would like to ask some questions on what to do. I was on vacation the past week and didn't want to respond to be honest. This car is my daily so I can't have it down for more than a day or two. Tomorrow I'll re-do the ground wiring and check all the connections on the alternator again.
__________________
TANIN AUTO ELECTRONIX
262-456-4147
contact@taninauto.com
www.taninautoelectronix.com
TANIN AUTO ELECTRONIX
262-456-4147
contact@taninauto.com
www.taninautoelectronix.com