It's likely... mine would drop down and the lights would dim. Apparently the stock unit doesn't put out very much, lol. Check into a 3g Alternator swap... loads of info on here. Or you can go through PowerMaster and get a one-wire style self-exciting one. I got their 150amp and it rocks.
if theres nothing else on, besides the engine, and its going up and down, I don't think its a need more power issue. i think the stock alt puts out 70ish amps
Figure this:
Ignition system & computer = 12 amps
Fuel pump = 12 amps
Exterior lights = 15 amps
Fan (heater or A/C) = 15 amps (can run between 5-25 amps depending on setting)
Radio & instruments = 10 amps
Wipers = 10 amps
That's grand total of 74 amps from a 65 amp alternator. Talk about overdrawn at the bank!
You guys with idle problems could same a lot of time chasing your tails if you would go through the Surging Idle Checklist. Over 50 different people contributed information to it. The first post has all the fixes, and steps through the how to find and fix you idle problems without spending a lot of time and money. I continue to update it as more people post fixes or ask questions. You can post questions to that sticky and have your name and idle problem recognized. The guys with original problems and fixes get their posts added to the main fix.