Okay so recently swapped my high milage motor out that ran with a low mileage b20b. The car cranks but wont start. Fuel pump is not priming when key is turned over and I'm not getting any spark. I have a jumper harness for an 8pin to a 10pin harness on my dizzy and I did the ckf bypass for the no crankshaft sensor. The grounds are all good and the ground on the thermostat housing is good and tight. The ecu and fuel pump fuses are also good. I'm stumped any help would be great as the car had fuel and spark before motor swap.

 

Helpppppp!

 

welcome to the forum. have you reset the ecu? one way is to remove the positive and negative terminals off the battery, keep terminals away from the battery posts. place the two terminals off the battery together for 10-20 seconds and then reinstall the terminals one at a time. then try to start it. if it starts, let it run for 10 min or until the cooling fan turns on. ( do not let the engine overheat )

 

Yes the battery wasn't even hooked up for whole duration of the swap. I literally swapped out the old motor that ran and had spark and fuel for a new one and now I dont have any spark or fuel.

 

Update: check engine light dint come on at all when key is turned to on position. Rpms dont bounce when cranking and the main relay dont seem to be doing any clicking or getting any power. Like I said though everything was functioning before swap

 

did you get a chance to reset your ecu, it needs to learn your new engine. having the battery disconnected for an engine change is good and safe.

 

Okay, the first thing I was going to ask was if the check engine light comes on when turning the key to the "ON" position.
So, now need to determine if there is power and ground going to the ECU.
Need schematic to find pin out. Otherwise how to determine which pins to check?
See if ECU relays have power.
Next would be to check to see if there is a 5 volt reference voltage
Sometimes it can be shorted and shut down the ECU
TPS throttle sensor usually has a 5 volt reference

Wait, swapped out old motor for this one?
Same type motor? ECU?
Looking for compatibility issues??
Did new engine come with harness?

Sometimes connector pins get bent
Could check connectors for problems

 

Yes swapped in a lower mileage b20b jdm motor. Same thing just jdm. I used the original harness and original ecu. I checked to see if I was getting power to the 15amp fuse in the under hood fuse box for the ecu and when key is turned I dont get a 12volt reading. But the power coming from the battery into that fuse box is 12 volts. I have all brand new grounds and the g101 ground is clean and tight.

 

Sounds like the ECU isn't being powered up??
I don't have any schematics so it is difficult to tell you what to look at next.
Maybe an ECU relay??

 

Well that's my thoughts as well but I dont know of an ecu relay. Just a fuse in under hood fuse box. I know there is a main relay but that is also not clicking or doing anything