Hey guys, I finished up my swap from the original 305TPI to a carb'd 383 stroker in my 86 trans am. I also did the serpentine swap and cs130 alternator. The car has a brand new battery, alternator, starter, and battery harness from innovative wiring.

I bought this adapter with the resistor ( ) a year ago for when I was going to go with the cs144 but decided to just switch from the stock 12si to the cs130.

Here is where I think I made a mistake. for some reason I thought to myself, "since I'm not going to the cs144 I'll have to cut out the resistor and splice in wire." which I did do. the car ran fine for a couple weeks but now it wont start without a jump box and will die once the battery runs out of power. I'm wondering by me cutting out the resistor, did I fry something in the alternator? I spliced the resistor back in and tried it but it still isn't working. I took the alternator to autozone and it tested good but I'm wondering if their machine is capable of picking up a problem such as that.

With the car off I'm getting around 11.5volts at the battery and back post of the alternator. as the car is running the voltage slowly dips down to the point where the engine sputters out. I have an MSD box and an aftermarket fan controller running the stock single fan, those are the only two additional draws I've added to the car.

Thanks for your time.

 

I'm not sure what's up with your current setup but I have the serp system on my 86 Trans Am and did nothing other than move the wiring over and change to the CS130 connector. Works great and I've been running it that way daily for several years. Initially I ran a used stock alt, then a new ACDelco unit, and now I have the PowerMaster XS Volt unit which is running on it internal "smart" VR that has adjustable voltage output and the remote sense/field flash is disconnected. It's a neat little unit and works perfectly as a one-wire. Though I had no problems other than old wiring slight voltage drop prior to running this unit.

GD

 

 

There's something with some of the CS130s where they need the alternator or charging light in the dash to excite the alternator. Since most thirdgens have a gauge instead of an idiot light, there usually isn't a light there to perform that function. The resistor very well could be there for that reason. The alternator bench test rig should have a button and corresponding light to test that function. Anyway, do some Googling about converting from the SI alternator to the CS and you'll probably find a lot more info than my feeble memories.

It'd also be a good time to double check all your battery cables and grounds are clean, and tight.

 

 

If the alternator tests good at Autozone, then you should assume that your problem is the car's wiring.
Don't just put the CS-144 in as is. You might damage it. Correct the wiring problem.

 

 

 

If all else fails, bypass the car's wiring, and wire up the alternator like you would on any hotrod.

 

Sounds like you need to fix the ignition switched circuit.

I did nothing really - I cut off the old connector and wired in the CS130 connector. No resistors.

Removing the ECU should not affect the fan relay coil power lead. Should be the same as it was before.

GD

 

 

 

Found a pretty odd thing today, I looked at the back side of the fuse box under the driver side dash and noticed that there's a brown wire going into the cooling fan fuse pin and the terminal on the other side of the fuse has no wire connected, essentially making the fan fuse a broken circuit. the previous owner did have the fan wired to constantly run so maybe this is why he did that. there's an aftermarket alarm installed like spaghetti in there so its possible they ripped the wire out when installing that, causing the previous owner to just hard wire the fan.

any idea what color wire is supposed to connect to the opposite side of the fuse?

 

It's probably not that a wire is missing. It just looks that way because the fuse block uses bus bars. In other words, there's a brass strip with several contacts that goes to the power side of a few different circuits. There only needs to be one wire connected because the terminal carries the signal from that one wire to several fuses. The fuse connects the bus bar to the individual circuits. It can look really odd because the bus bar has a pair of tabs on the back side for every part of contacts on the front side, and they're all crimped, even the ones without wires in them.

 

 

 

Yeah, in theory. The ECM fuse, and INJ 1 & INJ 2 fuses should all be 10 amp fuses, hot in start/run/bulb test. You'll probably want to check a wiring diagram for your specific car to be sure there's nothing running off those fuses you might need.

 

 

Wooo! Well done!

 

well a pretty big problem showed up,

I went to move the car out of my garage to build a workbench and when I started it the dash volt gauge was at 18 volts, I quickly blipped the throttle a couple times and it dropped down to 14. I built the bench and when I started it back up it did the same thing. I've read a couple threads about it so I'm going to check all the wires tomorrow after work and make sure everything is tight and in good working order. Just figured I'd share what happened in case anyone comes up with some ideas while I'm at work.

 

Here are the wiring schematics from the 86 HELM for the 86 Firebird TPI.





I've used an Alternator adapter similar to the one you posted a link to in the past and it was pretty much G-T-G,... but that was a Camaro !

** You should re-visit the C207 dash-to-ECM harness connector again and be sure to provide GROUND to any Black wire on the C207 connector. I know some early Birds lost ground for the the speedo VSS Buffer when the ECM harness was disconnected and this might be true for other electrical stuff too.

C238 is as easy spot to connect to a 'switched' ignition wire. A lot of folks call it a junction block,.... should be located behind the drivers side kick panel. ORANGE wires in 1 column are HOT at ALL times and PINK in the other column are HOT in RUN. Most cars have at least 1 open slot for additional accessories.




P.S. Like others have already said, good grounds are real important ! Double/Triple check any grounds to painted parts !

 

I finally got around to checking c207 for any ungrounded black wires and it appears that the only one that needed to go to ground was the black/white vss wire which you helped me determine a little while ago. other than that, theres no other black wire in any of the c207/ecm harness