I just finished installing a replacement engine from an '88 5-speed in my GT. When I crank it I get no spark.

I removed the engine harness through the firewall and when I reinstalled it I have one connector left over inside the car next to the ECUs that I can't find a mate for. It is a 3-pin connector with only 2 pins populated. Is there supposed to be an unused connector?



Also, the '88 engine does not have the temp sensors in the heads for the ICM system that cuts off the injectors if the ignition stops working on one bank or the other. Is it possible that not having the temp sensors plugged in could cause no spark?

My ICM system has the relay below plugged into it. There are only 3 prongs on the relay. It appears that the original ICM relay is mounted on the LH/EZK bracket and was unused on my car when I bought it. You can see it in the upper right of the first pic of the connector I can't find a mate for. It is the clear box with a gold strap holding it to the bracket.

 

Ok more info is needed,
what year harness did you use on the engine?>
where is the ICM connector?
That 3 pin is not used, so leave it alone.

OK i see you had another thread and this is with the same car and the same issue.
SO it might be better to close this thread and work off the other one

 

I used the original '89 harness from my car. The only change from stock that I have made is the engine is from an '88 S4 5-speed.

The ICM connector is plugged into the relay shown in the bottom pic as I found it when I bought the car.

Good to know that the 3-pin connector is not the source of my issue, but I still have no spark. One possible cause eliminated. Who knows how many more to go.

I started a new thread because this title more directly addresses the current issue/

 

This was the culprit. The brand new CPS sensor I installed because the connector on the old one was starting to fall apart. I swapped back in the old sensor and it fired right up.

I guess the $50 FAE sensor isn't such a bargain vs. the $200 Bosch or Porsche part.

 

Glad you got it. FAE = Fails And Enrages!

 

Wow. These eastern parts are getting that bad?

 

There is a drop-in replacement from a Jeep that works. Bosch and everything, just a bit longer tail. I cant recall the part number, but a quick search would find it.