fox body running rough after see 130 amp alternator conversion

PakstinN

Member
Jul 17, 2014
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alright so I am having a weird issue I cannot get to the bottom of. A couple of weeks ago, I went to take my mustang on a cruise and as the cruise progressed, the car became almost undriveable, I took it back to my shop and after a few minutes of looking things over, I discovered I had a bad alternator. I then went and purchased an see 130 amp alternator, the full conversion kit actually (I may also note that I decided to buy a bigger alternator due to the fact I have an upgraded sound system and it was drawing lots of power from the charging system) The install went fine and everything went on like it was supposed to, but when I started the car back up, the problem was nearly unchanged, the car was totally undriveable, it had an unbelievable miss that would make the car stall and surge horribly while cruising, so I parked the car due to frustration and came back a few days later. long story short, when I went back out the car and drove it, I realized it was now totally drivable so long as I did not use any of my accessories or my headlights, I figured this was because I had a bad ground, so I went through my entire engine bay and accounted for the grounds (everything is all good now, at least according to my knowledge), after I tightened up a loose ground, I noticed that I could now use the radio, but if I combined the radio and the headlights, it would start running like sh** again. I then went deeper and thought maybe somehow the computer was fried, I happened to have a spare computer laying around, but the computer change didn't fix it either. the car now runs okay with the headlights on dim and the radio very quiet, but if I push it past 2000 rpm, it will start missing and sputtering. My questions here are; has anyone else had a similar problem? and what am I possibly overlooking that would fix this issue? if I have been too vague about any part of my explanation I would be more than happy to elaborate. I just want my car to run!
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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polk county florida
What conversion kit did you use for the alt?
look up the surging idle checklist, your problem may have little to do with the alternator but the checklist will help you isolate the issue without throwing parts and money at it randomly.
 

PakstinN

Member
Jul 17, 2014
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What conversion kit did you use for the alt?
look up the surging idle checklist, your problem may have little to do with the alternator but the checklist will help you isolate the issue without throwing parts and money at it randomly.
I used the SVE 130 amp alternator full conversion kit that late model restoration offers, I will also look at the surging idle checklist, thanks!
 

Boostedpimp

15 Year Member
May 8, 2003
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NJ
Sounds like two different issues to me but I have to ask.. What pulley are you using on your 3g alternator?

Have you verified that your battery is in good health?
 

PakstinN

Member
Jul 17, 2014
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23
Sounds like two different issues to me but I have to ask.. What pulley are you using on your 3g alternator?

Have you verified that your battery is in good health?

I’m using the pulley that came on the alternator when I got it, never measured the exact size.

I have checked the battery, it’s over 12 volts when the car is not running (I have also had several different batteries in the car which changed nothing) and the charging system is putting out around 14 volts, so I don’t think this issue is from lack of juice
 

Mstng93SSP

You have a nice rear end there Dave.
15 Year Member
Nov 29, 1999
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Mililani, Hawaii
In the beginning of the post you said you were cruising and the car became undriveable. You changed the alternator and the car was still the same which leads me to believe the alternator was not the problem. And the new 130 amp alternator is also not the problem. Run the codes and start from there.