Jdm swap not coming to life

[Redtape]

So I have a 2004 wrx with a jdm ej205 single avcs and a jdm 2001 sti ecu swapped in that wont start.

Im trying to break down each problem 1 at a time. The engine will crank over but not start. When I removed the spark plugs to check for a spark, I noticed that they were all covered in gasonline except for the plug in cylinder #3. The fuel pump primes and fuel pressure is around 46 psi but i guess cylinder 3 isnt pulsing? Does anyone know what could cause this? Another point work mentioning is that the engine will backfire while cranking, however i double check the timing and all the marks line up.

Im fully aware that this is not the only reason why my engine isnt starting, but like I said im taking it 1 problem at a time.

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[What could go wrong]

Assuming fuel is the issue, maybe check the injector for that cylinder? try swapping #3 with a known good injector? If that doesn't help then it's just a matter of working back from there (is the injector getting power? if it is is it the same power as a "good" cylinder? is the fuel line clogged? etc, etc)

That might not be the right problem though, if it was a bad injector it would *probably* start and just run on 3 cylinders (IE like dog****)... I had a similar issue when I put my motor in and it turned out to be ECU related...

I would swap an injector, see if the problem moves, if it does it's the injector, if it doesn't I'd triple check your wiring and ECU compatibility before running through the whole fuel system but that's just me.

[Redtape]

I checked the injector, the problem was the lower injector seal came of causing the injector to “fall” into the tgv housing and spray fuel out the rail. I put the seal back on, now all cylinders are spraying during cranking but still no start .

Im 100% sure the issues is no spark but idk why im not getting a spark

[What could go wrong]

Originally Posted by Redtape

I checked the injector, the problem was the lower injector seal came of causing the injector to “fall” into the tgv housing and spray fuel out the rail. I put the seal back on, now all cylinders are spraying during cranking but still no start .

Im 100% sure the issues is no spark but idk why im not getting a spark

sorry for the late reply, if it's still an issue, just pull the fuse for the fuel pump, then pull the plug and coil out of the block and crank it outside the engine, just to triple check that spark is actually the issue... if it isn't sparking at all check your plugs, then the coil, then the wiring, etc... its possible you fouled the plugs while testing other stuff, or the wiring is just messed up somewhere upstream...

This still feels like it might ECU issue to me TBH, could be getting spark at the wrong time, coils could not be getting enough signal, could be a wiring issue, the tune could just be garbage... IIRC not all coils are created equal in terms of how much voltage and for what duration or whatever they need, which is controlled by the ECU, so check that your base map is accounting for whatever plugs your using... I could be wrong on that though, it's been a minute since I looked into the spark system...

Good luck with the search, keep us posted on what turns up, ill sub the thread