I replaced the thermostat in my 96 Civic DX 1600 and now the car won't start. I pulled a spark plug and don't see any spark when the engine turns over. Any ideas what I might have done to disable the spark? There is a ground wire on the third bolt in the thermostat housing, but I cleaned the surfaces so I'm pretty sure I have good ground.

 

check the ground wires that bolt on the thermastat houseing

 

do u have onther dizy laying around

 

The ground is critical. Measure voltage from the ground wires to battery (-) with the key on, should be nearly zero. Does your CEL cycle on and off like it should when you turn the key on but don't crank? That indicates the ECU is getting basic power and ground.

Coils can blow at any time, take the distributor cap off and hold a grounded test wire near the coil output. If you only get weak yellow sparks, replace coil.

 

Thanks for the replies. I checked ground again - pushed connector firmly on to the fan temp sensor and everything works fine now. I'm not sure which fixed the problem but it starts and runs great like before.

 

Thanks. Good info that I'll file for next time. The third time I tried to start it after I posted the problem it worked fine. I've started it 20 times since with no issues. Not sure if the ground finally made the connection or if pushing the connector firmly on the fan temp sensor made the difference.

 

The fan sensor only controls the fan. It will not cause a no-start.