Now Voltage Fluctuating?
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,138
Likes: 139
From: Port St Lucie Florida
Now Voltage Fluctuating?
Starter is up everything tight, took out this morning, had it up to 13.8 for a time about 5 miles it starter to go down. The neg connection was loos so I tighned it up with pos connection. Goes down to 11.9 again after new starter.
During initial start up though it read 13.5, when driving the volts on DIC drop, any suggestions.
During initial start up though it read 13.5, when driving the volts on DIC drop, any suggestions.
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
Starter is up everything tight, took out this morning, had it up to 13.8 for a time about 5 miles it starter to go down. The neg connection was loos so I tighned it up with pos connection. Goes down to 11.9 again after new starter.
During initial start up though it read 13.5, when driving the volts on DIC drop, any suggestions.
During initial start up though it read 13.5, when driving the volts on DIC drop, any suggestions.
Explain what you did change so others can evaluate and comment.
Mr. Sam
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,138
Likes: 139
From: Port St Lucie Florida
I am going to measure battery while idle, then run a cable from alt directly to batt, measure will come back with results.
Also where is the ignition switch located? Where do I find it. I can check that too.
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,138
Likes: 139
From: Port St Lucie Florida
I just took the car to the store to get gas and the voltage on DIC is all over the place. There is def something wrong from 11.7 all the way to 15.1 and just throwing out numbers, its not consistant. Any Ideas? Thanks for your responses.
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,138
Likes: 139
From: Port St Lucie Florida
Just a backround, I cleaned the ground this morning underneith the battery, it was really dirty and retighten it.
Last week before I changed out the starter, I ran a direct cable from the alt to the battery reading 14.1
Now this afternoon did the same thing and DIC reading 12.9, I don.t understand this. Everything is correctly tightened at the solinoid at the starter, I retightened the grounds, dont know where else to look.
Race Director
Joined: May 2003
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From: Iowa
St. Jude Donor '03 thru '26
With the car off, a good battery should read about 12.6 volts (at the battery, not the DIC). When you start the car, it should jump up to over 14 volts, preferably 14.4 volts (again, at the battery, not the DIC).
Please post what results you get doing these two simple measurements.
Please post what results you get doing these two simple measurements.
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,138
Likes: 139
From: Port St Lucie Florida
With the car off, a good battery should read about 12.6 volts (at the battery, not the DIC). When you start the car, it should jump up to over 14 volts, preferably 14.4 volts (again, at the battery, not the DIC).
Please post what results you get doing these two simple measurements.
Please post what results you get doing these two simple measurements.
I am really wondering if its the alt. A couple of days ago I took the red pos off the alt and put a direct line to the batt and it was reading at 14.1 for a few minutes.
While car was warm today did the same thing and I got 12.9 from pos alt to pos batt. Don't know what else to do.
I am researching the forum tring to find answers. Thoughts?
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Melting Slicks
Joined: Jan 2009
Posts: 3,275
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From: Miami FL
It would be useful to know what voltage you have at those 3 places (DIC, battery and alternator) "simultaneously" (or as close in time as possible).
Melting Slicks
Joined: Jul 2013
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From: Anaheim CA
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,138
Likes: 139
From: Port St Lucie Florida
I do know whats wrong, it called narrowing it down my friend. Nothing wrong with what I previously posted, looking for advice and those who has gone thru this before.
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,138
Likes: 139
From: Port St Lucie Florida
I am leaning now poss alternator, when cold starts its around 14.1 volts, then as it warms up beginning to fluctuate like 13.5 12.9 11.8 15.1 14.1 etc etc. I tested a cable from alt to battery still fluctuating. Tested battery stable 12.2 volts.
Does anyone know is it difficult to rebuild your own alt? Whats all involved or just buy one.
Does anyone know is it difficult to rebuild your own alt? Whats all involved or just buy one.
Melting Slicks
Joined: Jan 2009
Posts: 3,275
Likes: 739
From: Miami FL
As I said before, it would be good to have the 3 separate sets of voltages (one from DIC, one from battery and one from alternator) when what you describe is happening.
You will need a multimeter to read from battery and alternator.
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,138
Likes: 139
From: Port St Lucie Florida
Where are you getting these measurements from? Are they coming from DIC, or you are using a multimeter and measuring directly at battery or alternator?
As I said before, it would be good to have the 3 separate sets of voltages (one from DIC, one from battery and one from alternator) when what you describe is happening.
You will need a multimeter to read from battery and alternator.
As I said before, it would be good to have the 3 separate sets of voltages (one from DIC, one from battery and one from alternator) when what you describe is happening.
You will need a multimeter to read from battery and alternator.
During initial start up (cold start )the DIC reads 14.1 volts, until it warms up then it become irratic back to 11.7 then 12.5 etc etc.
I just took the alt to get tested at autozone and oreilly's and it passed.
Last edited by corvet786c; Oct 18, 2015 at 05:19 PM.
Le Mans Master
Joined: Mar 2011
Posts: 6,835
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From: Columbia SC
I figured that out from his Post 4 after all I had done on his first two posts to ID how to diagnosis that related issue.
By all means OP, don't provide any background info like I requested in Post 3 for everybody.
I have been out of here since Post 4. I like to help people and I have more than enough others I am dealing with. Spending 2 to 3 hours on this Forum each day with people who like being helped keeps me very busy. I like working with 4 or 5 Forums over several car types I have and that adds to that time. If I was smart I would spend more time with my paying clients. It pays way better and they are grateful.
Mr. Sam P.E. (The Old Fart)
Thread Starter
Melting Slicks
Joined: Sep 2007
Posts: 2,138
Likes: 139
From: Port St Lucie Florida
I figured that out from his Post 4 after all I had done on his first two posts to ID how to diagnosis that related issue.
By all means OP, don't provide any background info like I requested in Post 3 for everybody.
I have been out of here since Post 4. I like to help people and I have more than enough others I am dealing with. Spending 2 to 3 hours on this Forum each day with people who like being helped keeps me very busy. I like working with 4 or 5 Forums over several car types I have and that adds to that time. If I was smart I would spend more time with my paying clients. It pays way better and they are grateful.
So I am on these fourms to get help and try to diagnose what could be the cause, testing and replying back with results.
Mr. Sam P.E. (The Old Fart)
Sir, what information have you given me in related to my problem that I have not already tested and tried. I am constantly replying on the info I have and pin point what could be the possible cause. Instead of complaining about what other posts I have up, comment, if u can help, if not then go somewhere else.
Last edited by corvet786c; Oct 18, 2015 at 06:02 PM.