Could this be <PERSON>?
Most well known as a book series, <PERSON> is a tween boy with an encyclopedic knowledge of minutiae who uses them to solve various crimes or mysteries.
The book series spawned a TV series of the same name in 1989, aired on HBO. The Wikipedia link above lists the episodes, and I have quoted them here:
The series began with an hour-long special, "The Case of the Missing Time Capsule", and subsequent six episodes were 30 minutes long.
1. "The Case of the Missing Time Capsule" (hour long special first aired on March 2, 1989, to kick off series and aired over 200 times on HBO) "Idaville is celebrating its 100th birthday by opening a time capsule left by the town founder. But before anyone can discover what riches it contains, the capsule is stolen! When <PERSON> and his friend <PERSON> investigate, they find no shortage of suspects.
2. "The Case of the Missing U.F.O." (Case #529) aired first on 3/9/90 . Something eerie is going on in Idaville when a flying saucer and flashing lights appear in the night sky. <PERSON> and his side-kick <PERSON> interrupt their relaxing camping getaway to brave the unknown and uncover the mystery of the U.F.O.
3. "The Case of the Amazing Race Car" (case #524) first aired 3/16/1990 <PERSON> looks like a sure winner in a funny car derby, that is, until someone steals his car. Encyclopedia Brown steps in to solve the mystery.
4. "The Case of the Ghostly Rider" (case #525) aired 3/23/1990 The ghost of the WildCat Kid has returned to haunt Old Glennville, can <PERSON> and <PERSON> with a little help from <PERSON> save the day?
5. 167
"The Case of the Flaming Beauty Queen" (case #932) first aired 6/5/1990. Encyclopedia Brown investigates who set the fires in the library and whether the case of the hidden money is a scam or not.
6. "The Case of the Incredible Culpepper" first aired 7/10/1990. This episode does not seem to have been released to VHS. The big <PERSON> magic show is spoiled when a mountain lion belonging to The Incredible Culpepper is stolen. <PERSON> and <PERSON> are immediately on the case and identify several suspects. With their typical detective skills they soon solve the crime and return the lion to <PERSON>. The magic show finally entertains all the good folks of the town- Thanks to Encyclopedia Brown.)
7. "The Case of the Burglared Baseball Cards" (case #523) first aired 9/1/1990 Encyclopedia looks into the late night theft of a priceless collection of baseball cards.
8. "Encyclopedia Brown, The Boy Detective in One Minute Mysteries" released straight to video (This includes 5 of the <PERSON> stories from the books, "The Case of the Scattered Cards", "The Case of the Foot Warmer", "The Case of the Bitter Drink", “The Case of the Civil War Sword", and "The Case of the Great Merko". This was also released to VHS.) 167