Won't Idle, then will, then won't.
 

So its kind of a complicated situation, but could use some insight.

So a few months ago I sprung a coolant leak about a day before I had to leave for Afghanistan. So I took the intake manifold off and fixed the coolant leak and quickly threw it all back together. Well when I got it back together it idled super high, but I didn't have time to deal with it then.

So I'm getting closer to the point of coming home from the stan so I asked my friend to take a look at it told him something probably just wasnt hooked up right so it shouldn't be a huge deal.

Well he smoke tested it and found a leak, fixed it, idled perfectly the entire rest of the day.

Went to start it up today(the next day) and it idled at 1800rpm again.

Was wondering if anyone here had any insight that could help my friend out. I hate that I'm not there to work on it. The closest rotary specialist is over an hour away from where it is stored now, and after the wife's DD just required over 2k worth of work I'm trying to avoid some huge repair costs on the rx7.

It sounds like the vacuum lines need to be checked over according to the diagram. When I first got my fd, there were vacuum lines that were completely severed yet the engine would occasionally run just fine and sometimes have a high rpm. Once I checked it with the diagram and replaced all the broken lines, it ran great.

Some of your lines could be hardened from the heat. When this happens as it does on all FDs at some point some pop off under turbo boost. You may want to do a complete vacuum line replacement when you get back.

I know you said your friend fixed the leak, but it sounds to me like an air leak around the intake manifold/ throttle body / elbow which would make sense if you had it off just before the problem started.