I have after market VDO gauges with my 4.9 conversion. The alternator does not charge and the temp gauge pegs then returns to normal when I start the car. I have read several of the threads on the charging problem but I am wondering if my two problems are related? Also is there a direct connection between the terminal on the alternator and the "L" plug that plugs into it and goes to the terminals with the fuseable link?

Never mind, I found the answer to the "pegging" problem, still need help with the charging.

Do you still have the charge warning light on your dash or was that removed when you swapped gauges? The alternator won't charge without that circuit in place.

I don't have a great pic of the circuit, but the regulator relies on a current draw through the bulb for the alternator to charge.

CS130 (4.9) alternator or one from your Fiero, and if from the fiero what year/engine?