My si body that i picked up had a blown motor but i have a wrecked hf with a good motor... So thats were the plan began. Now the motor is in and hooked up. I was excited for the first attemp to crank, but it didn't crank. The fuel pump is not kicking on whenever the key is turned on. I changed the main reley to two different ones, I also took off the fuel rail just to make sure and still nothing. what should i do and what should i check? i also took the ecu out of the hf... The previous motor in the si was a v-tec sohc zc running in obd0 off of a b16 ecu. I didn't know if you should tell you that or not.

 

So you're running your MPFI IM right?

Also, see if the fuel pump itself is messed up.

 

yeah, its the 8 valve hf motor... but yes its mpfi. whats the easiest way to check the fuel pump? also, i dont hear any clicks whenever i turn the key over.

 

turn the key to the ACC position (second turn of the key in the ignition). listen closely for a humming sound, also your main relay would click once you turn your key to this position.

If you cant hear it, get close to the fuel tank and listen again.

 

just as a side note, you might want to swap heads over to make any decent power...

but i agree check your main relay

 

you could check for continuity at the fuel pump too.
i had close to the same problem... you say you've changed out the main relay though. it was the main relay that was the problem for me.

 

just a heads up - you can't use the HF engine harness with the Si chassis harness - you need to use Si engine harness, unless you want to repin the connectors - the car won't start with the HF engine harness and will have a Check Engine Light with a code 15

do you have the ground wire connected at the thermostat housing? - it is the ground for the ECU, the Main Relay and most of the sensors

 

ok i'm gonna check the fuel pump today. i changed my main relay twice but i still don't hear the click whenever i turn the key.

im not trying to make much power, really im just trying to make it run and then work out all the kinks.

yeah, i'm using the si harness. the check engine light is on but the ecu is not blinking, so im confused. yes, that was one of the first things i did was ground there..