No start after rebuild

[Dequavis]

I've recently rebuilt my 1990 non turbo engine with manual transmission (somewhat of a part list at the bottom) i converted it from a N/A to Turbo as well as the model year basically because i could only get 92 turbo engine harness and a 94 ECU with v3 ecmlink off facebook market place. I believe i have all my sensors replaced with 91-94 that are different such as Ignition coil, CAM, 91 Throttle body and sensors attached, MAF, added a fuel injector resistor pack, I got my C-67 connecter by the ECU figured out and wired correctly, and that's all I can think of now. But I'm running into a no crank no start problem. I tested my starter and it worked and tested correctly. I'm thinking it could be the ECU that I bought because my CEL doesn't light up for 5 seconds on the first and second time on turn my car on after connecting the battery but then it'll light up all the other times light up and turn off like normal. I don't know if that's just because it's not booted up all the way or what, I also tried to start it by running the starter to the battery but im not getting any fuel pressure out of my new walbro 255. My MPI is doing some weird stuff too the housings is loose around it and it'll kinda clam shell open and it'll turn the car to Accessory mode without the key being in it, so can a MPI cause a no crank too? One more thing the ECU i bought part number is for a 94 turbo manual but the guy I bought it from said it was for a 90 so I tried swapping pins 6 and 14 on ecu just for the hell of it and still nothing, and my engine harness is for a auto transmission but I looked and the doesn't matter I don't think atleast..

CP Carrillo piston, K1 pistons rods, Eagle crankshaft, ACL bearings, a machine and bore on the block. For the head I also got in machined down and I have BC 272 cams, BC springs with titanium retainers, Supertech valves and guides, ITM revised lifters. I have a CXRACING 16G for my turbo kit for now until I can understand turbo systems more and upgrade, pink top 560cc injectors, and a walbro 255 pump

 

[Drewpy Dawg]

You’ve got a challenge on your hands. Lots of variables, any one of which could be the source of your problems. Yes, a faulty MPI relay can cause starting issues. The relay is connected to the starting circuit and it powers the fuel pump and the ECU. I would start by testing the relay with a meter to make sure it’s operating and sending power everywhere it should or swapping in another as a test. If the relay checks out ok and still no start move to the next link in the chain such as the starter relay, ignition switch, etc. Make sure you have continuity from one end of the harness to the other. It’s going to be a process of elimination but you’ll need to test every link in the chain.

 

[Dequavis]

You’ve got a challenge on your hands. Lots of variables, any one of which could be the source of your problems. Yes, a faulty MPI relay can cause starting issues. The relay is connected to the starting circuit and it powers the fuel pump and the ECU. I would start by testing the relay with a meter to make sure it’s operating and sending power everywhere it should or swapping in another as a test. If the relay checks out ok and still no start move to the next link in the chain such as the starter relay, ignition switch, etc. Make sure you have continuity from one end of the harness to the other. It’s going to be a process of elimination but you’ll need to test every link in the chain.

I'll run some tests on that sunday. I know i have another MPI laying around somewhere from my Talon, but it's killing me because I don't know where I set it... so I might go off this Thread. Homemade relay if i cant find that other mpi ill do that sunday. I cant see myself spending the $100 for a new one if I'm not even sure that's the problem