Help! Voltage doing funny things

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

JubjubW

Full Access Member
Joined
Apr 23, 2011
Posts
257
Reaction score
3
Location
Wausau, WI
So yesterday I replaced the power window motor and made sure all my plugs were right where they belonged when I put the door back together.... I also replaced plugs with AC Delco Iridiums and Taylor wires... and also replaced the blower motor - made sure the ground was TIGHT...

Last night drove home saw no funny business, nor today in the daylight when I was driving... however I was coming home in the dark, got on the highway and getting up to highway speeds the truck starting loosing voltage and the lights dimming... cruising they would come back to regular... the voltage stays a steady 14 volts before this... tonight it would drop down to roughly 12

Stopped at Oreillys and they came out to test the battery and alternator - I bought the battery from there 4 months ago and no problems when I converted it all to top post...also got a rebuilt alternator (from a reputable shop that rebuilds alternators - not one off the shelf - so all the parts put in were put in that day) Guy tested battery at full strength - no problems 100% charge
when he tested the alternator however the lights all flickered BUT the alternator came out the first test at 54 amps... second test 71 amps... so the alternator is working just fine... and the voltage all read 14.5

and on the highway - there were times when I would turn my signal on to change lanes and the lights would dim with that
any ideas?

Possibly thinking of taking out the blower motor... the skin where the ground mounts was painted - So I had hoped that the screw tapping its way in was enough - but I could take it off and grind some paint off

and was also remembering - the speaker in the passenger side wouldn't work at first - maybe thinking I accidentally crossed the tweeter and speaker wires and plugged them in wrong - could this cause the problem? I am hoping it will last til next weekend... we had a funeral visitation today and tomorrow the actual funeral to go to, and all week my hours suck and really no time to work on it.... =\
 
Last edited:

purple 'hoe

Full Access Member
Joined
Jul 6, 2011
Posts
695
Reaction score
3
Location
Green Bay, Wisconsin
I'd start by double checking everything you did yesterday. See if you have a mistake somewhere. Are you sure it's actually dropping voltage, or are you going by the dash? Because I know mines off by a lot for voltage.
 
Last edited:
OP
OP
JubjubW

JubjubW

Full Access Member
Joined
Apr 23, 2011
Posts
257
Reaction score
3
Location
Wausau, WI
I'm 99% sure its voltage, my headlights dim, dash lights dim, battery light comes on

----

If I get a chance tomorrow I will tear the door down again and check it....

one thing I got from reading, it may be the belt tensioner? it only has less than 2K miles on it

also no misfire issues truck still runs like a top
 
Last edited:
OP
OP
JubjubW

JubjubW

Full Access Member
Joined
Apr 23, 2011
Posts
257
Reaction score
3
Location
Wausau, WI
That would rule them out then. Do you have any audio equipment running when it drops voltage? Anything plugged in? HID's? Extra lighting?

Stock radio - on or off - does it under acceleration - and as I stated above I may have accidentally plugged the tweeter plug into the speaker and the speaker plug into the tweeter - dunno if that would make a difference
Heater on/off - same
lights - well I wouldn't be able to see my voltage guage in the dark... and the only extra lights are on the cap visor - the tails are LED - and the halos are LED
 

SunlitComet

OBS Jedi-Do Good
Joined
Sep 30, 2010
Posts
16,206
Reaction score
188
Location
unknown at this time.
those alternator tests don't sound right you should have gotten more from it.

---------- Post added at 01:47 AM ---------- Previous post was at 01:46 AM ----------

also do you have any burn marks on hood above battery area?
 
OP
OP
JubjubW

JubjubW

Full Access Member
Joined
Apr 23, 2011
Posts
257
Reaction score
3
Location
Wausau, WI
No I do not have any burns. I did not get a chance to tear things apart today, family things went really late. Tomorrow morning I plan on taking it back to my grandpa (the guy that rebuilt it) and hes got a wide variety of tools to hook up and test it....
 

Ceejkay

Full Access Member
Joined
Apr 8, 2011
Posts
570
Reaction score
24
Location
Ft. Lauderdale, FL
did you remove the battery when you did all this work? maybe you didnt connect the ground tight?

also i think alternators are supposed to read the amps they are rated ie most of ours are 100amps plus..
 

Forum statistics

Threads
132,436
Posts
1,868,117
Members
97,114
Latest member
AdamxYukon
Top