I have 98’ 2,2 liter subaru Impreza outback sport. A day ago I was unable to start it. I would turn the key and a few light would come on- the clock the battery light… they would sort of fade on and as I turned the key I would hear a fast clicking sound. I did some turning of the stearing wheel took it in and out of gear ect. and it started right up after a little wait. No whining or cranking like with a dead battery. It did it again later that night but started right up after a while and today it wouldn’t start right away and I figured I should clean and check the battery . The positive connection was very corroded and covered with blue and white crust. I cleaned it off and brushed it. I needed to wd40 the screwed but I uncrewed everything and cleaned that too. It started right up but I barely got a block before the car jerked/ lurched a few times (as with old spark plugs) as I turned around the engine light came on blinking. IN the manuel, it says this is an indication of a misfire. Of course the blinking turned to a solid check engine light on. I came home and parked. Now is this symptomatic of bad battery connection, maybe ignition issues or other issues. Would it be related to and electric issues or my futzing with the battery.
On a side note I had been getting a check engine light periodically coming on over the last year every few month. I took it to the shop and they reset the code twice seeing some sort af vapor code/emission code… Finally they checked for leaks with smoke and replaced a few seals or something but never really found the cause.
Did you clean the post and the terminal? Wd40 is conductive and I wouldn’t spray too much. If you coat your battery it will short from post to post. If I had to guess I would check the ground cable. Try to look under the insulation. If it is green and corroded it may be a huge source of resistance. I have stripped back an entire ground cable (3 ft) and it was completely corroded. This was for the same symptons you are having.