ok, i have already searched ALOT, and cant find anybody with a similar problem. Ok, so i have a 1987 rx-7 gxl. It has the omp and the air pump off of it, besides that everything is stock. It would never idle below 2000rpm for crap, and that was at the lowest. And it would only idle sometimes, i had to heel-toe alot during breaking. So, i decided to spend my weekend ripping apart my intake, cleaning it all up, replacing all the vaccume lines, painting everyting, checked all the injectors. Put it all back together slowy, i am POSITIVE that all of the vaccume lines are hooked up, so i start it up, and the SAME ****!!! im gonna kill somebody or something (not really, that was sarcastic), 10 hours for nothing.

so, i decided to check my BAC with a ohm meter, everything checked out ok. I checked the TPS also, everything checked out fine, but i put on a extra one anyways and it still is doing the same thing. this isnt the first time ive had to figure out a idle, and ive gotten pretty good at it but this is kickin my ***. So, if somebody can please help me out i would greatly appreciate it. MY freind said someting about a idle air control valve but i looked in the FSM and couldnt find it. Any help would be appreciated!

 

anyone?

 

"idle air control valve"
Someones mistaken nomenclature for the BAC valve.

Anyway, your problem sounds like it could be an air leak. When you removed the air pump did you block off all the hose connection points? And seal the block-off plate? Check the AFM connector and all air hose (not vacuum hoses) attachment points that connected to the air pump, intake hose, the BAC valve and the AWS solenoid valve.

 

On the back side of the throttle body is an actuator for high idle during warmup. It has a coolant hose running to it, and one running from it to the BAC. The dashpot is there also. Take a screwdriver and push down on the linkage arm which rests on this actuator and see if the idle goes down. If it does, then you might have to replace the thermowax pellet in the high idle actuator, or try bleeding the air out of the coolant line going to it. I just spent 2 days hunting down a loping idle at 1200-1500 rpm and it was that thermowax actuator.

 

The BAC valve IS the idle air control valve. And just because the ohmmeter specs out ok doesn't mean it isn't sticking internally. It just means that the coil windings inside aren't open or shorted. If idle speed is your only complaint, try swapping out another BAC from another car. Check the "for sale" section on the forum or Ebay. If you also have a rough idle and stalling, grab a propane torch (don't light it of course). Have someone sit inside the car and hold the idle high enough to keep it running. Open the valve on the torch to get some propane flowing. Aim the (unlit) torch at the air intake inlet. If the engine speeds up and smooths out, it is running too lean and you need to use the propane to find a vacuum leak such as intake gaskets, cracked vacuum lines etc. If it slows down and gets rougher, it's too rich and that is a bit more difficult to track down. Also if the idle is rough it can be caused by low compression so don't rule that out.

 

that could definetly be it. I did block off everything that had to do with the Air pump invcluding that peice on the LIM. I have 2 extra s4 intakes so i will try using a different BAC and if that doesnt work ill try "Aaron J. Williams" idea. THanks for the help

 

tryed a different BAC and still nothing. The thing is... it doesnt idle at all. In revs it is fine after 2200 or so, but below that its just all messed up. Could it be something in the wireing? bad grounds? It isnt something as simple as a air leak, way worse than that.

 

tried a different ECU, did some grounding work, didnt change a thing...... what else is there to do!

 

so i guess nobody knows then... oh well.. i guess ill just figure it out on my own. wish me luck!

 

Borrow a neighbor's propane torch and do what I said to do in my earlier post. Just don't light the torch and it's all good lol.