Volkswagen Repair: VW engines, ca emissions, california emissions

Question
What is the difference between the 100 and 105 Horsepower 1.8 litre engines in 1991 Jetta

Answer
I think it had to do with California emissions, and non-California emissions engines.  They should also have a different engine code...three letters, on the cylinder head.  If they have the same code, then one had a secondary air pump(the one for California), and the other one did not.  I hope you find some other source to corroborate this, but I just ran across a similar emissions question at work about a 2000 Golf.  It turned out to be Ca. emissions.
Hope this helps, Michael.  Good luck.