Check engine light every few seconds, how to check?

[harister]

Ok, so I have a problem - there must be a solution, but I cannot see it.
The check engine light comes on, then goes off, every three seconds. When it's off, the engine runs fine, when it's on, the RPMs cut in half, it misses, and it has no power / won't go into top gear. It's a 1993 Sport with 71k that had been sitting.
It has had a complete tune up, new fuel tank, sending unit, plugs, wires etc, and I've put 2k miles on it. This began in wet weather.

The engine is not storing codes. With the engine off/ignition on test, it just flashes 111, but with the engine on test, the light doesn't stay on long enough to collect a reading.

I'll start with the coil pack, but does anyone have any suggestions after that?

 

[vq5speed]

Check your connections on your sensors like MAF and TPS could be loose make sure they haven't backed out. I had this happen with my MAF connector the snap clip was broken from taking on and off many times so it was not together tight. Had to put a tie wrap to keep it pushed in.

 

[FR-425]

Kinda sounds like the ol' low voltage/bad battery thing again.

i.e. voltage is dipping low and the computer is rebooting over and over and over. .. . .

Also known to be a bad PCM relay.

 

[EMBRACETHEHATE89]

Mine sat for about 3 months before i kinda started daily driving it. The check engine would flash on and off quite a bit. It finally just stopped doing it one day.