'90 240sx hatch won't start after engine trans swap

[CJams]

History:
- Engine blew (4 years ago) 90 hatch
- Replaced both engine and auto trans with good engine and manual trans from wrecked '90 hatch.
- Good engine and trans worked fine right up till we pulled it.
- Swap went well. Jumpered the wires together on the top plug behind the fuse box in engine bay. All threads say the car should start. But It doesn't.
- When the key is turned all the way to start the car everything goes blank as if the clutch isn't pushed in. There's nothing.
- So I don't think it's the manual swap wiring stopping it. This car hasn't been active for 4 years so I thinkit may be something else. ie: missing fuses, relays, etc..
- I tried the ECU troubleshooting and got this... turn on ignition, turn ecu knob fully clockwise and it blinks one, then 2times, then 3, then 4, then 5. I let it cycle like this 4-5 times and then turned the knob back counterclockwise. When turned back counter clockwise both the red and green lights come on and stay on for ever.
- The manual says to check all the wiring, i did and everything seems to be plugged in.

Does anyone have a better troubleshooting tree/method to figure out where the faulty wiring is?

Any suggestions?

No wires are currently connected from the manual transmision to the car. And we are still using the auto trans ECU.

Any help would be greatly appreciated.

[dccse3k]

4 years? first thing would be to make sure your starter works, try hot wiring it straight from the battery. you have a good battery in it right? also check your grounds w/ a multimeter and touch it from the negative of the battery and w/ the continuity test touch random bolts on the engine.

also you are right, the transmission wiring or lack of has nothing to do with it.

[CJams]

Thanks. yes, 4 years in a garage.

The starter worked before we pulled it from the other car. We pulled the motor and manual trans together and never disconnected the starter. Everything worked on the running car. I drove it in to the garage and parked it right next to the rig with the bad motor so everything should work fine. The battery is a brand new red top. I was going to hard wire the starter just to see if it jumps a bit, but it should.

I also did a visual inspection on all of the electrical connectors in the engine bay, everything seems to be fine.

Except there is a "Low Pressure" switch plug that is not connected. I don't see where it shoudl connect. but I did short this plug together to see if that helped, no go.

[dccse3k]

well try hotwiring the starter while the key is in the on position and see if it starts. If not i'd first make sure you have spark fuel and compression and then once you get it started trace your ignition wiring to see where the problem is. post up what happens once you try hotwiring it. you can buy a push button switch w/ long wires hook one up to the +12 and the other to the positive plug on the starter(not the one that you have to put the nut on).

and the low pressure switch i believe just controls the oil light in your dash so that probably wouldnt affect starting it but that plug is right near the oil filter

[CJams]

Turned on the ignition, then ran a 12v wire directly to the starter relay wire on the starter. Messed with the throttle since I was in the area and viola!!! She started and ran. Even with 4 year old gas in her. I put some stabilizer, a gallon of fresh 92octane, and a can of seafoam first. But she runs. So the problem is in the starter relay circuit somewhere. All of the dash lights seem to be working fine though.

So.... Anyone have starter relay circuit troubleshooting tree cliff notes?

Also might need to swap the rear end out since I heard chatter in 4th and 5th gear at about 45-50 during the test drive. Something aint right back there.

Thanks for all the help. Forums are great.