Hi guys, completely new here but was told I could maybe find some good advice.

At 240k, my engine blew a piston rod. I bought a Japanese crated engine and successfully had the old engine removed and had it installed through personal friends. Everything is good and connected, but there seems to be an issue with the idle. I know that could mean a lot of things, but I can reply and tell anyone what I've already tried.

Again, the issue is the idle. I get 2 error codes for the knock sensor and iac air intake control. When I turn the car on, the idle rises to about 3.5k then drop between 1 and 2. Does that consistently unless I put the car in drive or reverse. Park and neutral have the surge issue. If I drive, the car functions fine until about 30mph or 3000rpm. Then the check engine light flips and then it starts to surge once I'm in going below 15mph.

I don't see or hear any vacuum leaks, and I'm personally not a huge car expert.. But I'll explain anything I've tried. I can send videos through email as well, thank you guys.

 

Manual EX has a 2-wire IACV. Automatic EX and all DX or LX have a 3-wire IACV. I don't know what your friends did, but generally you should remove any JDM intake manifold that comes with the engine and reuse the US one that came with the car.

The knock sensor screws into the back side of the engine block above the alternator (the sensor above the oil filter is not it, that is the oil pressure sensor). You may need to remove it from your old engine if the new one didn't come with one. Some blocks do not have threads tapped in the hole for the sensor.