My check engine light blinks quickly 3 times on my 1990 legacy wagon

SOURCE: fault code

The information I can find on this shows a code 15, not 16. It shows it as a problem with the #1 shift solenoid or it's harness. Causing different internal transmission concerns. The book I found shows no code 16,this could be a miss print. Either way, this is a concern that appears to be an internal trans. problem.Good luck.

SOURCE: Subaru Outback - '03 boxer 2.5L engine sounds like a diesel

heavier oil if you are not in a cold climate. but before you do that have the oil pressure checked. We used to use a can of STP every once in a while on a motor in a dodge we had... nothing wrong with it... was just noisy.

Robert

SOURCE: loss of boost and engine check light on

Please have the computer scanned for codes. Autozone or Pepboys will do it task for free. It sounds like it could be related to your fuel sustem or exhaust. But I need more info to be more spesific. Good luck.

SOURCE: Catalytic converter is bad on 1995 Subaru Legacy L Wagon

dearship parts are high.you can buy a factory catalytic converter or universal converter cheaper at auto parts place.they basic the same parts the.dealership has same catalytic converter.they put their price and labor rate charge an hour your pocket book will be empty.i have used universal catalytic converter.had no problem with it.the only difference is universal converter body a little shorter.but has same lengh as factory.if check engine is coming on you cant turn it off .if computer showing you a code.you could have a misfire causing rich exhaust emission.that can ruin a catalytic converter have it scan.dealership charge you about $130.00 .you can have it scan at advance auto or auto zone.to see what pcm code is.it could be oxygen sensor somethinh minor.

SOURCE: 1990 Subary Legacy engine miss at idle

If you are getting a CEL (Check Engine Light) then figure out the code. This is an OBD-I engine so you need to connect the appropriate test connector and count the blinking lights. (Google Subaru OBD-1 codes).
Now as for your problem. Most common cause is the MAF (mass air flow sensor). The square box on the air intake. Try tapping it with a screw driver, the connect inside is joined only with solder and years of stress can crack the solder joint. If your engine stalls whenever you tap it, get a new one or rip off the cover and resolder the connect. Also check the IAC (Idle Air Control solenoid).