KA24DE swap running extremely rich.

[SlydWeis]

I have done some searching and nothing really hits the nail on the head.

I bought a 1990 240SX with the SOHC and manual transmission in it.

I gutted the car, pulled the motor and transmission.92 motor was originally connected to an auto transmission.Took the flywheel off the SOHC and put it on the DOHC.Put on new brakes and clutch.Swapped in a 1992 KA24DE with the 92 harness and ECU.The person that owned the motor before I did put on a new head and water pump.I removed the vacuum lines from the carbon canister, blocked off the EGR, removed the vacuum solenoids on the back of the motor.Ran a single vacuum line from the manifold to the FPR.The swirl control valves are open. The IAC works fine.I setup up the timing, it's perfect.I removed the A/C compressor and PS pump. Made a custom bracket and pulley setup for the water pump.I used the old coil, water temp sensor and starter.Car starts up fine, runs fine, but blows black smoke, it's running extremely rich.I unplugged the MAFS, water temp sensor, O2 sensor, and TPS, it runs the same regardless.New plugs, plug wires, cap, rotor, fuel pump, and fuel filter. Still the same problem.Im wondering if it could be the injectors, FPR, or maybe I need to use a new coil.The higher the RPMs the more it smokes. I can drive it, but I have a smoke screen with me at all times.

Any help is appreciated.

Modified by SlydWeis at 4:49 PM 4/3/2007
Modified by SlydWeis at 4:50 PM 4/3/2007

[FUNGC]

does it run smoother without the mafs? cause that happened to me. ended up being the ecu was messed.

[rogoman]

Check out the temperature sensor for the ECU; it could be bad or else it may not be connected.

[SlydWeis]

As for the MAFS, the Idle goes up with out it plugged in, from around 800 to 2k. And as for the Water temp sensor, i unplugged it and the car ran the same, i have a voltometer and I can go check it tomorrow.

[freakyjason]

have you looked at the timing? might it be advanced? just my .02

[SlydWeis]

Timing is dead on, checked it again. Got a new MAFS, and still the same problem. Cleaned the spark plugs and got all the black off of them. I cant get a reading from the water temp sensor. I dunno if my meter is broke or what. So I left it unplugged for now. FPR is fine checked that. I assume that when a sensor is disconnected that the ECU should have default mode. Out of ideas.

[SlydWeis]

I did some more to the car, checked the injectors, new fpr, timed it again - (dead on), bought Denso Iridium spark plugs, new O2 sensor. I did some more research, I think that since the ECU was from an automatic and now I'm running a manual, I read that auto run richer, and have problems with cold starts, aka my car. So can I do something to make it quit or get a tuning device like a SAFC to do the trick? Or might their still be something i am overlooking?

[rogoman]

The A/T ECU and the M/T ECU have pretty much the same fuel mappings so using an A/T ECU shouldn't make it run richer. However leaving the ECU coolant temp sensor disconnected will certainly make it run richer; if it's bad replace it.

[gnomes321]

I would try replacing the water temp sensor for the ecu, that can cause problems like yours.