nbanwart

For some reason my alternator stopped getting significant voltage to the exciter wire after a rather large electrical fire by the starter. So instead of spending money on a new ecu and or new wiring, I would like to rig my alternator exciter wire to a ignition-on 12v source. I have that taken care of a put a 470ohm 1/2w resistor inline as was suggested by another forum, however there is not enough current going through and the alternator is putting out little more than the bare minimum to keep the injectors firing. Does anybody have any idea what size resistor/lamp to put inline that would put the proper current in the exciter line?

Tuned Performance

iTrader: (92)

BigBadLou

iTrader: (3)

The reply above is correct. 470 ohms is way too much to excite the field coil. 50 ohms (47 normally) will be better. Make sure you use at least a 3W resistor (they are bulky).

EDIT: If your excite wire does not work, does your cooling fan relay have power? It comes from the same fuse.

nbanwart

Thanks! Just got the resistor and will hopefully install it later today...

Very interesting...no I do not believe it does. The previous owner wired up the cooling system to a independent switch. The fuses are all good however. Thoughts?

BigBadLou

iTrader: (3)

Any idea on how the PO wired the switch?
I would check the FAN fuse under the dash. If it doesn't have power (on either side), that would explain a few things. But if it does have power, I would recommend to fix your wiring to keep it stock.

nbanwart

Just got the chance to look at the PO's wiring, and it seems as if he capped the original radiator fan wire and ran everything else straight to the better. Both fan fuses are entirely intact. Does anything I said here indicate a problem with the original wiring, or do you think something would not work if I were to hook everything up to how it originally was?

BigBadLou

iTrader: (3)

You say the fuses are all good. But do they have power?
Specifically these two fuse slots: FAN & HTR A/C.
You mentioned an electrical fire by the starter so I am curious whether that interrupted power to the fuse box and why the PO wired the fans to the battery.

nbanwart

I looked and looked and looked and could not find a FAN fuse, however the HTR AC fuse does indeed NOT get power. I was looking around and found a capped black wire near the starter. Touching this to a 12v source clicks a relay directly above it...thoughts?

BigBadLou

iTrader: (3)

What relay is that? There are no relays by the starter, to my knowledge.
If you mean the starter solenoid, that would be a bad thing.
Or if there is an aftermarket relay there, please post a picture.

nbanwart

Not necessarily by the starter, moreso by the blower fan. I'd like to think it's the fuel pump relay but the fuel pump works great at the moment so I'm assuming that's not it.

BigBadLou

iTrader: (3)

The only relay by the blower fan is the high-speed blower relay and it should not be clicking unless you turn the fan to High.

nbanwart

The fan was on high, which probably explains why the fan was turning very hard. The wire I found, I assume it likely goes to a constant 12v source?

BigBadLou

iTrader: (3)

Yes, that stray wire should go to the 12V lug on the starter solenoid.
Just make sure that once you put it on, nothing in the car starts smoking. You don't know why the PO removed the wire in the first place. He must have had a reason. Fire hazard? Battery drain?

nbanwart

So after finally replacing components in the distributor, i'm still having charging issues. I'm only reading a 12v charge, and im getting around 1.2xx volts on the excite wire. Thoughts?

BigBadLou

iTrader: (3)

What voltage did you measure on the FAN fuse?

nbanwart

I just measured 12v to the fan fuse with the car running.

BigBadLou

iTrader: (3)

Find the brown wire (which carries the 12V from the FAN fuse) on the C100 connector and measure voltage there. Wiggle the connector if you have low voltage on the engine side, it might be just a bad contact.