I have a 1995 Civic that will not start after sitting overnight. I can get it started by removing and cleaning the spark plugs. The plugs are gassed up like the car is dumping gas into the cylinders. It will start and run fine after this. It is a civic ex with a 1.6 litre engine with fuel injection. Do you have any idea what the problem may be?

Thank you,

Tim

It might possibly be a bad TW sensor (coolant temp sensor). If the ECU thinks the engine is really cold because of a faulty TW sensor, it will dump lots of fuel.
I would also check the ground at the thermostat housing.
Can you start it by holding the gas pedal to the floor? (flood clear mode)

I was able to start the car once about a week ago by holding the gas pedal down, however, It didn't work last time. Yesterday I discovered that there was a lot of pressure on the fuel tank that was released when I opened the cap. This was after setting all day and it had not been cranked. I installed new spark plugs and loosened the fuel cap and the car started fine this morning and this afternoon. Fuel seems to be leaking into the cylinders after setting a while. VCould it be a bad fuel cap or pressure regulator?

Thank you

You could have an injector leaking or something (rare).
You could hook up a fuel pressure gauge and see if pressure is dropping quickly after key off (indicating a leak) or if the pressure is abnormally high (bad regulator - rare)
Fuel tank pressure isn't abnormal.