My problems seemed to start about 2 months ago. My 91 civic 1.5 4 sp man. 199k, uses about 2 quarts of oil every tank. Could afford in the last year new distributor, timing belt, redone head, oxygen sensor, radiator, plugs and wires, valve clearance adjust, all in the last 10k miles. I'll list every noticeable event as I'm baffled. This car has always started hard in the year I've had it but always started. Kept taking oil and chugging along. One day at 60 mph it seemed to go out of gear, only it didn't, just for a split second. Don't know the signifigance if any, but within a day it began to act up badly. Starts got worse, idle rough, sputter at acceleration and higher rpms, exhaust made chugging noise, motor vibrated, power and mileage were seriously decreased. Though the symptoms would get better and worse for no apparent reason, the vehicle managed to make the 80 mile round trip to work about 6 more weeks. Never during that stretch did it run great, but certainly got MUCH worse at times, refusing to break 50 mph and occasionally just stall out. Finally, one particualrly rough running night, I pulled in for gas. After a fillup, hoping to find it improved, it hasn't run since (two weeks now). Checked error code: 16 came up. Pulled plugs and cleaned, which were nearly unrecognizable, I assume due to oil consumption. Seem to have good spark. Timing belt looks OK (visually). The injectors appear to be pouring out fuel at an unusually high rate. I' ve read about main relay problems but assume that it wouldn't pump too much fuel, but simply fail. I'm not sure about that though. I plan to wake up today and work on the car until I give up on it entirely or it starts and runs well. After all, it's got a full tank:p Any ideas about what direction to go in would be appreciated.

Just a guess... it sounds like your piston rings have disintegrated or maybe cylinders aren't completely seated and you're leaking a lot of oil in with the fuel combustion. Does it spew heavy white/blue smoke from exhaust?

Yeah its done that for a year or so... the smoke is white

White smoke indicates antifreeze is being burned and that the head may be warped or cracked. A cracked head might also account for oil being burned. Has the engine ever overheated?

Code 16 indicates a problem with the fuel injectors. Since you can't start the engine, disconnect the 2-P connector from each fuel injector and measure the resistance between the two terminals. If the resistance is not 10 to 13 ohms, replace the injector. Then, reset the ECM and see if the engine starts.

You may want to start at the beginning and perform the tests, outlined in Sections A and B, below:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-46563.html