Car Stays "ON" Without Key and Gas Gauge Doesn't Work

[SeVa-S13]

Ok, well good luck solving this and if you do, I'll PayPal you a 6 pack.

I have an RB20 in my 89 S13 240 so there's naturally a bit of wire-splicing around to go bad. Up until recently I used the Skyline gauge cluster but it never really fit right so I opted to use the stock SOHC gauge cluster with a transplanted R32 tach so I can read the 6 cylinder signal properly. Well that worked ok for a couple days, then out of nowhere my temp gauge started reading pegged out even at ice cold. At the same time, turning the key to ON and letting the fuel pump bring the fuel system to full pressure would cause the care to stay on even once I removed the key. Now if I pull the key out before the ecu turns off the fuel pump because it's full, it works as normal.

Yeah, screwed up is right.

I tried using another ignition harness with the same result. Now, to make things even more ridiculous, if I unplug the plug that controls the temp gauge from the gauge cluster this problem doesn't occur. I thin that pretty much sums up that problem, onto the gas gauge...

This one's pretty simple-- my gas gauge doesn't work but I'm getting the same reading with a multimeter at both the fuel pump and at the cluster plug so I'm lost. Now when I replaced my fuel pump with a higher flow one the assembly didn't seem to wanna go back it so I kind of had to push it just a tiny bit get the screws in. Thinking back on it, this may have not been the best idea but it was 2am and I was tired. My gauge worked before the swap started and the fuel pump upgrade happened mid swap when no cluster was actually hooked up so I can't say when exactly things stopped functioning. I figured if I get readings at the pump and at the cluster it should atleast show something seeing as I have a close to full tank but it always reads as empty. I've forgotten the readings and from which wires but I'll do it again if need be.

Prease, help meh.

[SeVa-S13]

Ok, well let's try this then. Tell me how to figure out what the problem is. Using the stock harness' wire for the temp sensor to the ECU and tapping that wire causes the temp gauge to peg as normal. Now if I cut the wire from the sensor to the ECU and run a new wire from sensor to gauge, it works fine as it should. To make sure it's not the ECU, I then can touch that connection via a test light to the ecu plug and while it raises the tiniest bit, it still reads normally.

PLEASE tell me how to go about pinpointing the problem wire. I have a rather complex Mulitmeter testlight and stuff so just tell me what to do.

[slownslurious]

when you turn your car on, does it turn off when you turn the key off? When I turn mine forward to the accessory spot (radio and power windows work but engine doesn't start) if I turn it off it stays on... I have to turn it forward to start before I can turn it off.Also my gas gauge doesn't work.Odd coincidence.