You should see somewhere in the neighborhood of 12 ohms, but there are other ways that an injector can fail besides the coil.

Do you have a wideband? It helps to determine if it really is running lean or if the ECU is confused by a failing O2.

 

I should mention that I have done the O2 sensor less than 1000km ago as well. I do not have a wideband unfortunately. I should really invest in one though.

 

"T" in an analog gauge on the fuel line going to the rail to be sure you are getting ~40psi... it's not common, but possible you have a bad FRPS, so the ECU might think it sees 40psi, but in reality it could be a lower number.

 

So the injectors read almost 14 ohms exactly across the board with a .1-.2 variation.

 

That's fine.
What you don't want to see is a big variance, say three at 14.2 Ohms and one at 11.7 Ohms. That would indicate (or be a step in the right direction) that an injector is hanging open. Even is good.

 

I've swapped every single sensor with one that works and still have the idle issue. This is getting frustrating. I'm now thinking it's a mechanical issue.

I've changed:
MAF
IACV
TPS
O2 Sensor
Fuel Filter
Fuel Pump (SVT so really an upgrade)
FRPS
Checked the injector resistance and they read fine

The only code it throws is lean but it seldom throws it; like once or twice per race.

Any ideas?

 

Who did the tune for the car?
Ask them if they tuned out the fueling/spark changes that will occur to control the cat temp (over temp, the ECU will drop spark and lean fuel to cool the cat if EGT's get above ~900*F).
So it's not something the average user would see. But if you're racing at high RPM for extended times the O2 will get hot and it it hits the limit it will pull fuel/timing.

 

Cracked intake manifold that only opens up enough to throw a code when it is cold? Or throttle body? Or any mating surface in the inlet track?

 

I added an aftermarket catch can, with my PCV and valve cover going in one side, and the other side going into the intake. I was passing enough air when cold (forged pistons and big ring gaps) that the car was missing and running super lean, as it was routed to the intake after the MAF, so it was unmetered air.

When I removed the line to the intake and plugged it, problem (mostly) solved!

Just an FYI. If it's acting like a vacuum leak, it's probably a vacuum leak. Check everything post MAF.

Denny