I have a 2000 Civic EX that runs great but sometimes does not want to start. It cranks fine but spins over for a very long time before finally catching.


It usually cranks right up like it is supposed to.

The problem only happens sometimes, when it hasn't been run for at least a few hours. When the problem occurs pressing on the gas pedal seems to help. Sometimes it takes so long to start that the battery dies and it needs to be jumped off.

Once started it runs perfect right away, No missing, sputtering or odd noises, and it has good power. And it is not throwing any codes.


I have a fuel pressure gage on order. Spark seems good. Everything seems to be working fine when the car is running so hard to figure.


Any ideas, things to check? I don't want to just throw parts at the car but getting a little frustrated with it.

 

Could be the fuel pump relay module.
Does it happen more often when the car has been sitting in the hot sun?
If so, quite likely to be the fuel pump relay module.

 

 

It only happens when the car hasn't run for a while, and cold weather seems to make it worse.

The main fuel relay was already replaced. I just put a fuel pressure gauge on top of the filter housing and readings are in-spec, 32 psi, and 40 psi with pressure regulator vacuum hose disconnected.

I cleaned the grounds, replaced the coolant temperature sender, and replaced the spark plugs since they looked quite old.

Hasn't given any problems the past few days, we will see...