i just put a new motor in my 92 civic sedan (b18b swap)it already had this motor n the car when i got it. the problem: it takes forever to get it to crank & when it does it idles rough. when i give it gas it just bogs down but if i very slowly give it gas it will rev up & as long as i play with the gas it will stay rev up, but sometimes if i hold it steady at a high rpm it will cut off, and as soon as i let off the gas it cuts off. please help!!!!!!!

 

Very confusing post...

You just put a new motor in, but car already had this motor????
Which is it, you put a new motor in, [did a B18b swap] or it had a B18b in it and you replaced it with another one?

It takes forever to get engine to crank, but when it does it idles rough???
Crank = trying to start engine, "cranking to start" or "turning engine over".
Idling, [rough or not] = engine is already running as in already started after cranking to start.

You need to be a lot more clear on what it is that is happening for us to help. 94

 

the car already had the swap in it. when i try to start the car it will fire up and run for like a second then cut off. it does this for a couple min b4 it finally fires up and runs. it lopes a little when idling. when i give it gas it boggs down, but if i very slowly give it gas it will rev up until i let off the gas and as soon as i do it cuts off.

 

Intake Leak? WHich ECU ? any CEL??

 

When was the last time the fuel filter was changed?
If you have not already, check to see what kind of fuel pressure you are getting.
As asked, any CEL 94

 

installed new fuel filter when i dropped new motor in. didnt find any vac leaks. cel is on but doesnt flash any codes.

 

What is the fuel pressure? 94

 

have no way of checkin da fuel pressure right now. i'm thinkin its either da fuel pump or fuel pressure regulator.

 

so you did jump the ecu right?

 

yep i did & didnt get any codes. could da ecu b bad since its not flashin any codes?

 

i think i found da problem. i have no voltage at the map sensor. anyone know where i should start searching to find da problem?

 

if the map sensor has no voltage it should throw a CEL.....what ecu are you using? and make sure you didnt switch the plugs for the TPS and Map sensor

 

its da right plug according 2 da wires goin 2 da plug & da wire diagram n da haynes book. da cel is on but when i jump da ecu no codes show up. i wondering if the ecu might b bad(its a stock ecu). if not i get the joy of tracin da map sensor wires. i just hope this is da source of my problem.

 

simply try another ecu then..and its quite hard to understand what you are saying..use proper english

 

ok i traced the wires coming from the map sensor to a plug by the firewall and the fuse box(under the hood). its yellow/red, green/white, yellow/white wires coming from the map to this plug. they go into the plug but dont come out the other side. WTF?????