Help with no-start issue

[mini zilo]

I just finished removing all the automatic wires and sensors from my wiring harness, because the car is manual now. All I did was cut and remove the wires going to the sensors. When I reinstalled the harness, the car cranks but will not start. Although occasionally it will fire one cylinder while cranking.

Things I have checked-
-Spark on all 4 cylinders
-CAS and CPS-both plugged in
-ECU and dash plugs are in
-Changed Spark Plugs


Heres the intersting thing, when I pulled the plugs two of them were covered in gas and two of them weren't.

What does that mean? Does anyone have any suggestions?

-I haven't done anything to the car since it was drivable other than pull the harness

 

[nickclay9395]

you should check the MPI fuse and relay... also try connecting all the connectors you can that the car originally had... that should narrow down your search

 

[mini zilo]

Where is the MPI relay?

 

[snowborder714]

http://www.dsmtuners.com/forums/problem-diagnosis/263224-mfi-mpi-relay.html

 

[steve]

Joe, I'm afraid you don't have much choice but to use brute force at this point.

You will have to check each and every wire from the ECU to the other end of the harness until you find a break or a misrouted signal. That will cover much of the engine wiring harness but there are still some power and grounds you will need to also check. If you think about where you did the most surgery and start testing with those areas you might get lucky and find the problem without having to test every connection. I can't think of a simple magic bullet at this point for you.

While checking the MPI relay is a good common suggestion, the fact that the car fires a cylinder indicates that during those times the MPI relay is feeding the ECU power. A better indication is just that the CEL works during buld test and if the factory boost gauge goes to 0 when your not cranking. Both of those indicate that the MPI relay activated and provided power to the ECU. A person might have problems with the fuel pump side of the relay but The odds are really really low that the main power side works but the FP side doesn't.