I have a 93 Civic EX, When I go to start it it gives me trouble. I have to hold the gas in or pump it to get it to start, When it finally catches, it runs for a second like its miss-firing, Then clears up and runs smooth as can be, I can drive it around all day. Car has great power and no hickups once its running. I have already replaced the Distributor, TPS, Main Relay, and Map Sensor. Also Car is running on a p06 thats been converterd to p28. I have swapped the ECU out with a p30 i have just to see if it goes away but problem persist. Any help would be appreciated. Engine is a d16z6, Was just converted to 5 speed. The problem first started before the transmission swap, It would start up with out the gas being held but a have a slight miss-fire on startup for a split second and clear up, Seams now the problem is getting worse as it is requiring the gas to be pumped/held in.

 

Anyone

 

Just a hunch but look at I believe its called that ECT sensor. Its the 2 wire plug while facing the engine left side of head just above block. Mine was doing the same thing before I fixed that. I had to go to a junk yard and cut the plug and rewired to my car. Mine ran rough till it warmed up and then ran fine. Maybe you messed up the wiring when you took out the transmission?

 

Fuel pump might be going bad.

 

Yeah but would it not run correctly at all times if it was the fuel pump?

 

No

 

Unless you did some weird mod, you should have fuel injection. ( obvious I know ) So if it was fuel related, pressing the gas pedal wouldn't have an effect on how much fuel there is for startup whilst cranking I mean. But it def sounds fuel related. I would agree with the fuel pump, but add, it could also be the pressure regulator conflicting with the PCM/ECM