Visual identification of NA vs NB Alternator
 

Anyone know any easy way to tell the difference between an NA (internally regulated) and NB (regulated by ECU) alternator?

I built a turbo 1.8 using a Hydra Nemesis when they first came out. I can't remember if I used the NB alternator from my donor block or the NA alternator than came in my '99. It has been working great for years, but the alternator is crapping out on me now and, for obvious reasons, I don't want to buy the wrong replacement.

Thanks

Google?

Tried that and came up dry.

Go to Amazon or RockAuto, look at the pictures for a 94 or 2004. The Denso pictures seem to show the clearest differences...

There should be an identifying sticker on it.

I could be wrong, but I thought the plugs were different.

I know this thread is old, but just in case someone does run across it. The plugs are not different...there is nothing mechanically to keep you from accidentally putting an 99-00 alternator on an NA. It will however very quickly cook batteries and many other things. Ask how I know...

FWiW


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