boostinfc3s

i got my hands full guys, so i need some help. i recently burnt my old TII harness in my 88 TII so I dropped a s4 N/A harness in. everything works fine, except for my battery. My alternator is essentially new so i'm almost certain thats not my problem. I get nothing higher than 10 volts when my car is on, and the volts just continue to drop as i drive. could it be a grounding issue? if so, where should i start to look at? If i wired the harness wrong, where should i begin to look for the culprit? thanks guys

need RX7

iTrader: (4)

If I remember correctly, the alternator wiring is different between n/a's and TII cars. I think on TII's it's part of the front(?) harness, while on n/a's it's part of the emissions harness.

Just wait till HAILERS comes in here, he'll be able to tell you

no piston drifter

i dont believe it would be anything in the harness that would be wrong and not charge the batt. id look into the wire that goes from the alt to the batt. and if its not that then it would have to be your alt. simple as that. however i could be wrong. thankfully there are other guys in here that have been at it way longer than i have haha

boostinfc3s

thanks guys, im pretty sure the wiring is good too.. i was wondering if i run a ground wire straight off the battery to the chassis to the motor if that would make it any better? what kind of wiree should i be buying?

ICEY?

iTrader: (9)

try the wire you get with an amp kit.. you know... the big red kinda.

HAILERS

What wires are connected to the rear of the alternator? The two that came on the NON TURBO harness? Sorry, that won't work. Those two wires will not mate correctly with the Front harness on a Turbo car.

Or are you using original alt wires that were a part of the Turbo cars original harness? They come off the Engine harness and that at first glance should work. See if there is batt voltage on the two wires on the rear of the alt. The black/white and White/Black. Key just to ON, engine OFF. Pull the ENGINE fuse and the batt pwr on the Black/White should disappear. Then pull the Meter fuse and the batt pwr on the White/Black should disappear.

Engine OFF, key ON ...the large ouput wire on the alt should read batt pwr.

On a non turbo car the alt wires are a part of the EM harness.

On a Turbo car the alt wires are a part of the Engine harness (the harness that runs on the left side of the engine bay, NOT the harness on top of the engine.

You need to buy a cheap or costly digital meter and check the output terminal of the alt and also the two wires on the back of the alternator.

Fact is if you used a non turbo EM harness on a Turbo car you should be experiencing quite a few more problems. The non turbo EM harness does not mate correctly with the Turbo Front harness. Wires need to be moved around to correct that problem.

It's not a grounding problem in any way.

ON a series four, if the two wires are not connected on the back of the alt, the alt willl not get excitation voltage..........but most of the time if you quickly rev the engine high, the alt field will self excite and the alt will put out. That is a symptom, not a FIX. It won't be regulated volage output.

Key ON engine OFF......the large ouput wire on the alt should show batt voltage. It goes from the alt to the engine bay fuse box. It's bolted to that fuse box in the rear side. Under a plastic flap there. Probably not your problem though.

boostinfc3s

i've tried both the wires from the non-turbo and the turbo harness. its just not charging. any ideas how i can get this fixed before saturday?

bwtp

The pinouts on the alternator in the TII and NA are different for my TII swap i had to run my own wires and repin the alternator, im pretty sure you just have to do what I did in reverse? The NA has the altnerator wired in with the engine harness and for the TII it believe it is on the car harness. I would just take a look at the wiring diagram in the FSM and rewire the alternator.

boostinfc3s

i checked the voltage on the alternator, its getting 13 volts, i'm pretty ssure its a grounding iissue.. im gonna ground 2 4 gauge wires from the negative post through the chassis to the motor.. see if that helps