b18a1 swap in 90 ef running poorly. please help.

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Depriesticles

Depriesticles

Kids these days...
I dropped a b18a1 into my 90 civic hatch DX over the weekend and it went pretty smoothly until I started it. I did a mpfi conversion on the stock dx harness and converted the dizzy plug and everything and it will start and run, but it is running WAY too rich and it wants to die when I let my foot off the gas. It is also hunting and surging. I did a continuity test for the orange and white wires on the ecu, the two white wires on the harness to make sure they are in the right spot, and the blue/green and blue/yellow wires on the ecu. All the wiring is correct, but I just cant figure out why it is running so rich and crappy. I can drive it down the road, but its hard to keep it alive. Can someone please help me?

There is a green plug on the back of the motor towards the bottom that doesnt have anything plugged into it. There is nothing on my harness to plug into it so I thought I didnt need it...but I found the plug on the LS harness that is supposed to go in there. The wires coming from it are white/green and black. Does anybody know what it is and what it does? The mechanic who helped me says if it is a temp sensor, then it needs to be plugged in or the computer thinks your car is always running at -32F and will dump a bunch of fuel into it to compensate for the cold weather. Does that sound familiar to anyone?

Or can it be a vaccume issue?
 
what ecu are you using? do you have any codes popping up?

the connector on the back of the block not plugged in sounds like the oil temp fan switch. it was used on the integra but is not needed when swapped into a civic. this is assuming you are referring to the smaller plastic shrouded connector. if you mean the green plug with 2 prongs sticking out of it, that would be your coolant fan switch. that does need to be plugged in so that your fan will come on, and the wires on your dx harness will be back there for that.

the hunting and surging idle could be because of air in the coolant system. make sure you let the car idle long enough with the radiator cap off so that all the air pockets find there way out. be sure to have your heater on as well so that any bubbles in the heater core can escape. if that doesn't solve your problem then try cleaning the iacv and the fitv. the fitv will control cold idle and the iacv regulates idle after the engine has warmed up. so for example if the engine is surging when cold but not once warmed up, the fitv would be the culprit.

how to clean your iacv
***How-To Clean*** Your IACV a.k.a. Idle Air Control Valve - Honda-Tech

how to clean your fitv
*** How-To*** Clean Your FITV aka Fast Idle Thermo Valve - Honda-Tech
 
I am using a pr4 ecu. I found out the hunting and surgning, wanting to die, and running rich was because of vacuume lines not being hooked up properly, but I am still throwing codes 5 and 9. They are the map sensor and the number 1 cylinder position. Can someone tell me how to hook the map sensor up properly? And what is that black plunger deal next to it? Does that hook into the map sensor off a "y" connector and then run into a vacuume line? Also, does the fuel pressure regulator just plug into any vacuume line on the mani? Or should that be plugged into the map sensor too? I am at a loss on the vacuume for this motor.

I have noticed that the throttle response is slow too. It sounds like the intake sucks a bunch of air in, and when it hits the manifold it will finally rev, so it takes a second to respond. Is there a way to make the throttle response better?

Good news is that it runs now and seems drivable. I just am not sure if it is safe to drive while it is throwing those codes. SEMI-SUCESSFUL SWAP! This is my first one. Thanks for all the help!
 
stock, the map sensor has a T for some reason that goes to a dead end on one side, and then to the map port on the top of the throttle body on the other. i assume the plunger thing you're referring to is the evap purge cut-off solenoid valve located directly to the right of the map. the bottom part of it goes to a port on the back of the intake manifold, and the vacuum line coming out the side of the thing goes over to the evap canister. just run the fpr line to any open port that seems logical.

this should help

vacuumhoseroutingb18ama.jpg


you will have extra vacuum ports that need plugged off for sure, that i can tell ya for sure lol.
 
I have the map sensor plugged in where the diagram is showing and yet I am still throwing a code 5. Do I need to get the integra map sensor to make that go away?

Do you know how to fix the code 9 as well? It says its the #1 cylinder position, but I dont know how to fix that.

Thanks for all the help you are giving me by the way. I appreciate it.
 
Ah! Ive done it!

I managed to get everything situated (except for the code 9...but I hear I need a new dizzy for that). I Actually drove my car to work today and I made it without any issues. Lol. Ill post another thread with my finished project with pics and all if anyone cares to see it. Thanks for all the help.
 
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