Speedometer Problem and Check Engine Light

[Crysis]

My speedometer does not work on my 1994 SVX and I was wondering if there is a cheap place to take it or if anyone has any info. on how to fix it yourself. Also, is the speedometer mechanical or electrical? Any help would be appreciated.

Another problem with my car is the Check Engine light turns on and off randomly. I do not know if it is a bad sensor or not. There seems to be no mechanical problems with my car and I notice it usually turns on when I go up a slight hill. Anyone know the reason for this?