I've been having a voltage fluctuation problem recently it will charge 14.5 to 14.7 when the rpms are above 2700. But when the caR is at idle it will drop to 12.9 or so. Sometimes it will read 14.5 or 14.7 at idle and the idle seems to be around 800rpm or so. But when it is at idle and the volts are 12.9 or so it will have alower idle usually around 600 or lower, i notice a drop in the needle after pushing in the clutch when decelerating (ie. slowing to stop at a intersection or red light). I checked all connections and they were all clean and tight.

So i searched around and found some info about using a gsr alternator but i couldnt find any info about using an ls, gs, rs alternator. I picked up one in a trade for some parts and have it on hand for use. Its OBD2 so there shouldnt be an issue there, but i was wondering if it would be ok to try it and see if it fixed this.

Jsut generally looking for any info as to what could be causing this.

 

i had the same problem(you'll probably find in the search) about a year ago, my head was wrecked trying to figure it out & i'm still unsure as to what or why.
voltage still varies slightly now which i presume is normal but the idle does'nt dip & rise like it did.
i had a clifford G4 fitted which i had other problems with, clifford were good enough to replace that with a G5, since then my problems have ceased, i explained this to the fitter but he said it was highly unlikely that the G4 was robbing voltage.
i'm sorry i could'nt be more helpfull

 

There arent any aftermarket electronics that would cause a drain or anyhting of that nature.

I've been reading alot of threads and the helm along with a few other resources but i'm not really finding any info. I'm gonna run by advance auto when i get off work and get them to do an alt. test for me.

The reason i question using the ls alternator on my R is because i read somewhere tha the R alt. has different bearings to allow for the higher rpm the engine is capable of, probablly another myth ( we all know there are tons of those out there) but it does make me a little aprehensive. I assume obd2 alt. for b series will work though i mean the only downside i could see is the ls alt bearing wearing out faster.

 

testing the out-put is done at 2,000prm. If you turn to page 23-105 in the service book you would see.

 

yeah i saw the testing procedure. But i know its not charging properly at idle because the dash lights will dim. It hasnt always done that. but thanks for the helm refrence i will read that section again.

So is it ok to use the ls alternator on it or not?

 

I believe the only difference between alt is the gsr is made by denso and the itr is made by mitsubishi... If it were me, I'd give it a try.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by walker111 &raquo;</TD></TR><TR><TD CLASS="quote">I believe the only difference between alt is the gsr is made by denso and the itr is made by mitsubishi... If it were me, I'd give it a try.</TD></TR></TABLE>

but the spare i have is off of an ls, would there be any difference. its off of an 01 so its obd2.

 

31100-P75-A01RM ls
31100-P73-A01RM ITR
31100-P72-013RM GSR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nholmes &raquo;</TD></TR><TR><TD CLASS="quote">Speaking from experience regarding the USDM alternators, the Mitsubishi alternator made for our cars is unique. GS-R and LS alternators don't bolt up without some sort of modification, as for working in a JDM motor I have no idea.</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by localmotion &raquo;</TD></TR><TR><TD CLASS="quote">The alt's will bolt up but there is a difference in ampage output between the different models. Also the itr alt is made to handle higher rpm's.</TD></TR></TABLE>

I'm finding mixed opinions on this.... I know for a fact that I've used a LS alt on a GSR with no ill effects. I will go with my previous statement, if it were me, I'd try.

 

same thing i got, mixed opinions.

i'm gonna try it i'm not losing anything and its just laying around collecting dust. I did a visual comparison and there didnt seem to be any noticable differences.

i'll post back with results after i get the oem one off i'm gonna take it and have it tested, called and they said it needed to be off the car to test it. May be this weekend before i get a chance to do the swapping.

if you used a ls on a gsr and the gsr will work on the itr it should work in theory...