92 canadian prelude with JDM swap. HELP!

[halfhorsepower]

My friend has a 1992 prelude. Auto trans. They swapped out the engine for the 197 hp JDM one i think in 1997. Not sure which engine it is exactly or the year etc. I can probably find that out. The issue is a very fluctuating idle at times, sometimes very low all most stalling out if i turn the steering wheel (power steering pump) or if i push the brake pedal when in park. It does need an oil change desperately so i know that will help at least a tiny bit. What do you think the issue is? Not sure if they also swapped trans.

Also, sometimes i'll shift it into reverse and it will not engage. Engaging in reverse always takes a second or 2 as well.

The car wants to go fast, it can really get going quite quickly on the road, but it seems the engine & trans are not talking to each other properly. It does shift properly at speed, and if i floor it it properly revs and locks up properly in 4th gear as well.

HELP!

Thanks!

- Andy