Ignition Switch or ECU?

[9d1gsxintx]

I have done a lot of searching on this issue, and I am thinking it is the ignition switch. But here is the deal, I just replaced an engine in a 1990 GSX, and when the key is turned all I hear is the one time click of the starter relay. Well my 1st thought was the relay, but that turned out to be fine. I happened to have a starter button and tried to turn the car over, and I am also not getting any fuel. So my question is doesn this seem like ignition switch or something more serious, like maybe I just hooked up something wrong on the wiring harness, I have been out of the game for a very long time. I ordered a datalogger, and I guess I thought this would tell me CEL codes on a 1g, but either I am not doing something correct or it is not working. Sorry for long post, but I really appreciate any help or advise.

 

[94_eclipse]

Make sure you have the engine ground wire on. I forgot to hook it up on my brothers car and had the same problem, it wouldnt run.

 

[9d1gsxintx]

Make sure you have the engine ground wire on. I forgot to hook it up on my brothers car and had the same problem, it wouldnt run.

Yeah, I even went out and got a new ground wire and moved it to a better location, so should be fine in that dept. Thanks for reply.

 

[yokotabrat]

Does the check engine light come on when the key is first turned to "ON"? Does the boost gauge go to zero (assuming stock code in the ecu). If neither of these happen, the ecu is usually not turning on the mpi relay (which also powers the fuel pump).

 

[9d1gsxintx]

Does the check engine light come on when the key is first turned to "ON"? Does the boost gauge go to zero (assuming stock code in the ecu). If neither of these happen, the ecu is usually not turning on the mpi relay (which also powers the fuel pump).

The CEL does come on & the boost does go to zero, then the CEL light turns off. I crank but nada, just a click from the relay. It seems like I have been what I thought was an hour away for nearly a month, I am going stir crazy, and just hate spending money on diagnostics, . Thanks for reply.

 

[steve]

The factory starter circuit an a 91+ car is pretty simple if the car didn't come with the theft alarm. Ignition switch provides 12v on the ST pin that runs to the starter relay and its coil on a manual car or to the inhibitor switch on a automatic and from there to the starter solenoid. The manual has the other side of the coil for the relay connected to the clutch safety switch and then to ground. Both the relay and the switch are normally closed devices. So if you don't push the clutch in the current flows through the coil and CSS to ground activating the relay which disconnects the ignition switch from the starter solenoid.

If your hearing the starter relay click when you try and crank the car, it's breaking the circuit to the starter and it won't crank. You can try disconnecting the clutch switch and see if that fixes it.

 

[9d1gsxintx]

The car is a 1990, I bought it used, and I do believe it did come with a factory theft alarm, for mainly the reason that I heard only in 1990 on the M/T did they have a starter relay with those with the theft alarm. I will try your suggestion, and let you know, thanks a lot. Can you let me know if this also applies if it did come with an alarm even if it is disable/removed? Thanks.

 

[9d1gsxintx]

The CEL does come on & the boost does go to zero, then the CEL light turns off. I crank but nada, just a click from the relay. It seems like I have been what I thought was an hour away for nearly a month, I am going stir crazy, and just hate spending money on diagnostics, . Thanks for reply.

Well after going thru everything, I replaced the ECU with another one I had and now the car cranks, and is getting gas & spark, but it simply won't start. The car was bone dry on fuel, so dont' think it is a fuel issue, I put in 5 gallons of fresh 93 octane, and I verified I am getting fuel & spark, but lastly I figured air, so I removed my MAF, and cleaned everything, I cranked it while watching the turbo, and it doesn't move, but I can move it with my finger pretty easily. Any ideas what might now be the problem? Thanks

 

[9d1gsxintx]

O, one last variable, is I put a cyclone intake on, everything is hooked up that I can think of, is there anything that anyone can think of, as far as why car won't start now? Thanks.