M20b25 doesn't idle AT ALL

[beckr19]

Hey guys, I'm swapping a m20b25 into my 325e. I have all new wiring from the m20b25, and I bought two used ICV's off Facebook. I just completed the swap, and my car turns on and sounds great, but the idle is non-existent. I know it isn't a vacuum leak problem, because when my foot is off the gas, the car completely dies. I am just wondering if anyone has any idea for what this problem may be. I've read forums saying it could be the FPR, or the ICV, or the ICM. I know that the ICV works because when I turn the car on, the valve closes, but I am also curious if this is supposed to open once I turn the key. I did test that, and the valve did not even budge... so maybe that is the problem? I really have no clue whether that is normal or not. I hope you guys can help me out. Anything helps lol.

[MrBurgundy]

Well, it can be a vacuum problem.

If you open the ignition to the second position, you should feel a buzz from the ICV

Also, the 325i doesn't utilize any modules outside the ECU to control idle.

Another thing, the TPS and ICV plugs can be accidentally swapped

[beckr19]

I just reversed the tps and icv plugs. The buzzing went away and there was no improvement. So, I’m going to switch them back. Any other ideas?

[efficient]

you got the i afm?
when i got my m20b25 into my 325e, it wouldnt idle and only the throttle would keep it alive. my friend had my i afm and i put it in and it turned on no problem and idled well

[Lefty_lifestyle44]

Having the same issue right now on my b25 swap, although i'm nearly positive vacuum leaks are the main culprit. If you haven't already, go double check any possible leaks because they're a lot cheaper to fix than other stuff. Wouldn't want to go spend a bunch of money only to realize your intake boot is cracked.