93 240sx dohc running rich.....

[sidewaysdan]

i have a 90 240sx and put in a 93 dohc engine did all the wiring got it threw emissions but i am running really rich....new o2 sensor ....cat....adjusted timing still rich any ideas????

[rogoman]

The coolant temperature sensor for the ECU may be bad.

[sidewaysdan]

that could be it cause i was having random temp readings......i will check it out......

[R-Yahne_240]

make sure your o2 sensor is plugged in too you getting terrible gas mileage like 5-9mpg????? it happened to my boys car

[rogoman]

that could be it cause i was having random temp readings......i will check it out......

There are two temp sensors. Check the one for the ECU; it's the larger one.

[sidewaysdan]

i replaced the temp sensor that goes to the ecu doesn't seem to make a differance......any other ideas???

[rogoman]

You may have leaking fuel injectors. To test them, unbolt the fuel rail from the intake manifold and pull off the entire assembly. Keep the fuel hoses still connected and don't remove any individual injectors. Also keep the electrical connectors on the injectors. With the assembly now away from the intake, turn the ignition key to the run position WITHOUT STARTING THE ENGINE. Now observe each injector to look for leaks. There should be no drips.

Make sure you have at least 4 spare insulator rings for the injectors in case some are damaged during rail removal.