Took the motor/harness out of my 88 crx si to put in my new 90 civic si shell. Everything went great until I went to connect the driver side wiring harness. My harness has 6 wires and the 90 civic has 8 I disconnected the clip and connected the wires by color. I was left over with 2 wires a solid blue and a black with yellow strip. Went to start the car and it didnt want to turn over. I sprayed some starter fluid and it started idled and revved fine. The car will start up after it is warm but if it sits for more than 15mins it wont start.

Tried looking through wiring diagrams but cant find what im looking for. If someone has had a similar problem or knows what those wires are for I'd appreciate any help

oh and i already had the b16 swapped into the crx and everything was fine..

 

I think the crx si came with another sensor under the intake, I had this problem with my ZC, never used them and it worked fine, but maybe the B16 uses it. I'll look and see which one it is. I know it's on a wiring diagram for a 88-91 crx si. I'll let you know.

 

It's called the Fast Idle Control Solenoid Valve, probably why it won't start and idle when cold. I don't know if there is one on a B16, maybe someone knows.

 

ive been researching for a while today all I can find are distributor wire colors and if thats the case the black and yellow is IGN output and the blue is tach output. but the tach is working. Pretty sure thats on the other side of the harness though.

 

ZCHondaCRX91 is correct - the 89-91 Si had a Fast Idle Control Valve (FICV) on the back of the intake manifold - the 88 Si does not have the FICV - the wire colors for the FICV are blue and black/yellow - that is why the 88 has 6 wires and the 89-91 has 8 wires - the B16A does not have the FICV (the B16A engine harness also has the rectangular 6-wire connector at that location just like the 88 Si) - if you matched all of the six wire colors, your connection should be fine - you need to look elsewhere for the starting problem - check fuel pressure

 

if it was me i would just run the 90 si harness so its all factory and just run the needed vtec wires (i heard the harness are different between the 88-89 and the 90-91, and a crx has to go to a crx, and vise versa with the hatchs) when i did my buddys swap his shell didnt come with the factory harness, we tried to rig up the one that came with the swap but couldn`t ever get it right,(came out of a 88 si crx and he had a 90 si hatch) with the right factory harness it fired right up and ran great

 

just swapped main relay and it wasnt the problem.. goin to check fuel pressure tommorow thanks for the help

 

yea check the possible causes the wires are suposed to hook up to! Follow them to the source.
Sometimes researching things likes these leads no where. Pop your head in there and see what they go to? if you can.
It sounds like a FICV.

 

Do you get any CEL's? This will really help find the problem.