97 civic ex with 95 civic dx engine starting issues
 

I have a 1997 civic ex coupe with a 1995 civic dx engine in it and i am having some issues with getting the engine to turn over and run. I have tried both the vtec ecu from the car and the non-vtec ecu from the 95 and no luck. I added fresh gas too. I thought it was the engine not getting enough spark and i replaced the distributor which solved the spark issue but still didnt make the engine turn over. When i try to start the car all of the pullies turn but it appears they aren't moving fast enough. Not really sure where to go from here, thinking it might be the starter possibly or even the fuel injectors flooding the engine, but again this is my first civic project and its somewhat uncharted waters.

What exact setup do you have? The 1995 ECU is completely different from 1997, it's an OBD1 system instead of OBDII. What is typically done (for a daily driver) is just to swap out the engine itself-- the block and head assembly-- and reuse all the manifolds and electrical parts that came with the 1997 car.

A VTEC ECU will start and run a non-VTEC engine but it will throw a CEL when the rpm hits 5500 and it detects that the VTEC did not engage.

Basic stuff like compression, cam timing and firing order should of course be checked. Also disconnect the fuel return line (after the regulator) to confirm fuel flow, and get a sample of the fuel. These engines do NOT like to start on stale gas.

What engine harness is being used? What distributor is being used? I would expect problems if you simply installed the new engine and used a conversion harness at the ecu.

when we swapped the engines we reused everything from the 97 ex. It wasn't getting enough spark so i replaced the distributor (put the 97 ex on in) and that solved the spark problem (it gets a clean white spark when it fires), I am positive the firing order is right as well. I haven't run a compression test, but i pored half a cup of fresh gas in through the throttle and tried starting it. The gas in the car is in the 3 to 6 month range in age, thinking i should probably try so fresh gas. I have two ecu's for the car, the V-Tec one that came with the 97 ex, and an ECU from a 96 dx which is non-V-Tec. I tried with both of them and neither made a difference. The Harness is the V-Tec one that came with the 97 ex, I just don't attach the V-Tec wires when i hook it up, and i have some of the wires spliced together to bypass the crank shaft (not really as hard as some people make it out to be). Anyone think that it might be the ECU or the Harness causing the issue?