93 s13 wont idle and constantly dieing

[Wonkmobile]

So Im aware that theres atleast 20 threads on this but all the ones i've read don't seem to provide a definitive answer to the problem. so I bought this car about three weeks ago and was not having this problem when I bought it. about 2/3 of the time about 5 min after starting my car will randomly stop idling sputter out and die whenever I push in the clutch for too long or put the car in neutral it also take a few seconds to actually start up which is concerning. idle also fluctuates insanely it will be as low as 200 or as high as 1300. I ended up taking it to a mechanic because I had to get a bunch of other s*** related to emissions done anyway and i was leaving town for a little bit.The o2 sensor was replaced and all of my fluids were flushed and vacuum leaks were fixed. it seemed to drive perfect when I picked it up until about an hour later and it started all over again, i later discovered that my coolant in the reservoir was low and that there was a brown sludge sittin in it and that i was leaking some sort of fluid just behind the engine. my friends told me that I probably have a Blown Head Gasket but I researched that and I don't seem to be having any of the other symptoms, could this be what's causing my idling problem? and if so what do you recommend I check to make sure that I have a BHG (also this only started right after I changed out my fuel filter and put in coils so Im wondering if I may have been retarded enough to somehow f*** that up and my car in the process) thanks for any help!

[PapaSmurf2k3]

I'd start by checking for codes. It could also be a bad MAF.

[Bi0N3RD]

mess with your ECU screw adjustment to set idle?

[Wonkmobile]

Thanks but that motors scrap metal now. It ended up getting gnarly rod knock so I swapped it with an sr