So here is the story, I changed my oil pressure sensor because there was a leakage. It wasn't hard to change it, so i was curious and became stupid. I removed the intake manifold to get space to replace the oil pressure sensor,but some of the coolant fluid came out and spilled on the starter. After all the mess, i putted everything together, but the car didn't start. All i could hear was a " CLICK" sound when i turned the key to the start position. Immediately after the first start, i tried to start again; this time it didn't make any sound- no electrical current. So guys Please tell me what's going on. NEED YOUr ADVICES. I need the car to work. Thanks in advance By the way, the car is 94 honda accord ex

 

I would disconnect the battery. Remove the two electrical connections to the starter, clean them with something like WD-40 to get rid of the coolant. Dry them off. Reconnect them. Hook up the battery and try to start the car.

If you still hear the one click, you may have gotten coolant into the starter solenoid. You may have to remove the starter and clean the two contacts. It may also be a coincidence that your starter solenoid and contacts are worn out. Its a pretty simple replacement, but you will have to order the starter solenoid and the two copper contacts.

 

Did you remove the terminals from the battery when working on the car? If so you may have a corroded one. Turn the headlights on and hit the starter, if the lights go out when you hear the click then you have corrosion. Tap on the terminal and the lights will probably come back on. Usually it's on the battery terminals but could also be elsewhere like on the ground lug. Sandpaper will do the trick to clean it up, you want both surfaces shiny. If the lights stay on then probably the starter or the starter lug but seeing you get no click the second time my bet is on the battery terminals.

 

I took out the starter and cleaned it, but i didn't see any coolant in it, so i think the starter is good.
When i turned the key in start position i heard a click sound, after that everything went out completely, even the light didn't turn on or the radio. So i really hope it's the corrosion. But then i did change a different battery, and the same thing happened.

 

You have either a dead battery or bad or dirty battery cable most likely if the lights go out when you turn the key. I would turn the headlights on and wiggle the cables and see if you can get tthe lights to go out or on depending on what you have.