*cliff notes at the bottom for those who don't need all the details*

I finished my B18B swap last month, and it's been running fine since then. After starting it for the first time, I bled the cooling system by idling the car with the heater blowing full-hot until I stopped seeing bubbles, and the coolant level stopped going down. Since it's been consistently warm, I haven't used my heater since then. Last night I was coming home and it was a little cool outside, so I moved my climate control temp lever(I think intermix control is the technical name for it) to about the middle position without turning the fan on to warm up a bit. The engine was warmed up at the time(about 80-90 deg C, which is where it normally runs), yet after about 5 minutes of driving, I still felt no heat coming from my vents. So, I turned the fan on, and waited a couple more minutes - still nothing. Finally, while waiting to turn left at a light(still with no heat), my oh-so-wonderful CEL pops on and my car starts idling and driving like crap. So I limp the rest of the way home(about 2mi or so) and go to retrieve the code(s). It's a 14 - IACV, which I'm pretty familiar with since I dealt with that same code a couple years back with my old engine(kept throwing a 14, and I swapped several IACV's and bled the cooling system numerous times trying to fix what turned out to be a loose vac hose ). So I went over the obvious things - checked for loose vac lines and any vac leaks, checked to make sure the IACV plug was still connected and that the wires were OK, checked for coolant leaks and loose hoses - I found that I'd forgotten to secure the clamp that goes on the heater hose running to the heater valve on the firewall. Apparently it's been like that for nearly a month, but I couldn't detect any leak from that connection, and the clamp seems to be too small to fit over the end of the hose, so I just left it kinda sitting in the middle of the hose and put a pipe clamp on the end since I didn't want to deal with hot coolant all over the place. Since air in the cooling system can cause the IACV to go nuts, I figured there must have been some air trapped in my heater core, and when I tried to use my heater, it got into the rest of my cooling system and tripped the IACV code. However, since my coolant was still very hot, and it was late(past 1am, I had to get up at 6 for a class the next morning) I didn't try bleeding the cooling system, but I did reset the ECU and tried running the heater again. This time it didn't throw a 14, but it also didn't produce any heat. Happy that at least the code was gone, I called it a night and hit the sack. Then this morning when I was driving to school, I decided to try the heater again. About halfway to campus(it's about a 10min drive thru city streets and morning traffic) my CEL turns on again, and the car behaves like it did the night before, and there is still no heat. When I got home from school, I let the car cool down, then I proceeded to bleed the air from the cooling system by idling the engine with the radiator cap off and the heater blowing full-hot like I usually do. The strange thing is that I didn't see any bubbles come up, but the coolant rose steadilly as it warmed up and expanded, and I had to keep syphoning the coolant out of the filler neck by stuffing paper towels in there to keep it from running over. I let it idle for a good 10-15 minutes and saw no bubbles, nor did the CEL come on, and the heat was still nonexistant. While I was messing with the radiator and looking in the reservoir, I noticed a small amount of what looked like oil floating at the top of the reservoir. Thinking it was the headgasket, I ran a compression test and got 205 200 205 205, which are roughly the same numbers I got when I had just finished the swap. So, I figured it was just the leftover gunk that had been in my cooling system before the swap(old engine died a gruesome death, and I didn't flush the system prior to the swap). That brings me to where I am now - still trying to figure out what's wrong with my heater/cooling system.

Sorry about the long post, here are some cliff notes:

*swap done a month ago and running fine since then
*tried to use my heater for the first time since then and it doesn't work
*moving temp/intermix lever torward hot eventually throws a code 14-IACV
*tried bleeding the system - no bubbles came out

Any help or insights are greatly appreciated.

 

Check your tech thread

 

thank you, sir